# State of Arizona

Exceptional Event Documentation

for the Event of November 4, 2011,

for the Phoenix PM 10 

# Nonattainment Area

Final Report Prepared for

Arizona Department of Environmental Quality

Phoenix, AZ

January 23, 2013

# This PDF document contains blank pages to accommodate two-sided printing.

# Co ver image depicts suspended dust and haze in the Phoenix area at 1535 LST on November 4, 2011, resulting from

strong winds generated from an approaching cold front. This photo was taken by an ADEQ visibility camera from

North Mountain looking south toward downtown Phoenix. 

# State of Arizona

Exceptional Event Documentation

for the Event of November 4, 2011,

for the Phoenix PM 10 

# Nonattainment Area

Final Report

STI-912092-5547-FR



# Prepared by

Daniel Alrick

Angela Ekstrand

Briana Gordon

Hilary Hafner

Clinton MacDonald

Hilary Minor

Ashley Russell

Sonoma Technology, Inc.

1455 N. McDowell Blvd., Suite D

Petaluma, CA 94954-6503

Ph 707.665.9900 | F 707.665.9800

sonomatech.com



# Prepared for

Theresa Rigney

Air Quality Assessment Section Manager

1110 W. Washington Street

Phoenix, AZ 85007

602.771.2274

January 23, 2013

# Exceptional Event, Phoenix, November 4, 2011 Acknowledgments



# iii 

# Acknowledgments

The authors would like to acknowledge the Arizona Department of Environmental Quality

for helpful discussion and feedback during the preparation of this document.

# Exceptional Event, Phoenix, November 4, 2011 Table of Contents



# v 

# Table of Contents

Section Page

List of Figures ............................................................................................................................. vi i

List of Tables

................................................................................. Erro r! Bookmark not defined.

1. Introduction ..........................................................................................................................1

1.1 Report Contents .........................................................................................................1

1.2 Exceptional Event Rule Requirements .......................................................................1

1.2.1 Public Notification that the Event Was Occurring (40 CFR

5 0.14(c)(1)(i)) .................................................................................................2

1.2.2 Place Informal Flag on Data in AQS (40 CFR 50.14(c)(2)(ii)) ........................2

1.2.3 Notify EPA of Intent to Flag Through Submission of Initial Event

De scription by July 1 of Calendar Year Following Event (40 CFR

50.14(c)(2)(iii)) ................................................................................................2

1.2.4 Document that the Public Comment Process Was Followed for Event

Do cumentation (40 CFR 50.14(c)(3)(iv)) ........................................................2

1.2.5 Submit Demonstration Supporting Exceptional Event Flag (40 CFR

50 .14(a)(1-2)) .................................................................................................3

1.2.6 Documentation Requirements (40 CFR 50.14(c)(3)(iii)) ................................3

2. Conceptual Model ................................................................................................................1

2.1 Geographic Setting and Monitor Locations ................................................................1

2.2 Climate .......................................................................................................................3

2.3 Event Day Summary ..................................................................................................3

3. Causal Relationship .............................................................................................................1

3.1 Discussion ..................................................................................................................1

3.2 Summary ....................................................................................................................5

4. Historical Norm ....................................................................................................................1

4.1 Analysis ......................................................................................................................1

4.2 Summary ....................................................................................................................1

5. Not Reasonably Controllable or Preventable ......................................................................1

5.1 Background ................................................................................................................1

5.1.1 Control Measures ...........................................................................................1

5.1.2 Additional Measures .......................................................................................3

5.1.3 PM Rule Effectiveness ................................................................................4 10



# 5.1.4 Compliance and Enforcement Activities .........................................................5

5.1.5 Review of Source-Permitted In sp ections and Public Complaints ..................6

5.2 Forecasts and Warnings ............................................................................................8

5.3 Wind Observations .....................................................................................................8

5.4 Summary ....................................................................................................................8

6. But-For Analysis ..................................................................................................................1

6.1 Discussion ..................................................................................................................1

6.2 Summary ....................................................................................................................1

# Exceptional Event, Phoenix, November 4, 2011 Table of Contents



# vi 

# Section Page

7. Conclusions .........................................................................................................................1

7.1 Affects Air Quality .......................................................................................................1

7.2 Not Reasonably Controllable or Preventable .............................................................1

7.3 Natural Event .............................................................................................................1

7.4 Clear Causal Relationship ..........................................................................................2

7.5 Historical Norm ...........................................................................................................2

7.6 Not Reasonably Preventable

..................................... Erro r! Bookmark not defined.

7.7 But For .......................................................................................................................2

Video Links ..........................................................................................................................1

Ap pendix A...........................................................................................................A-1

Appendix B...........................................................................................................B-1

Appendix C...........................................................................................................C-1

Appendix D...........................................................................................................D-1

Appendix E...........................................................................................................E-1

# Exceptional Event, Phoenix, November 4, 2011 List of Figures



# vii 

# List of Figures

Figure Page

2-1. Locations of air quality monitors that recorded exceedances of the 24-hr PM

N AAQS and the NWS monitor at Phoenix Sky Ha rbor International Airport (KPHX)........ 1 10



# 2- 2. Location of sites monitoring PM on November 4, 2011.................................................. 1 10



# 2-3 . Drainage System of Phoenix, Arizona. ............................................................................. 2

2-4. Average monthly temperat ures and precipitation for Ph oenix, 1981–2010.

.............. ........3

2-5. Gusty south-southwesterly winds associated with an approaching cold front

transported dust north-northeastward to t he Phoenix area on November 4, 2011. .......... 4

3-1. Visible satellite image from 1600 LST on November 4, 2011 (GOES-West),

depicting a strong cold front across the We st Coast...........

.................................. ............1

3-2. Phoenix area air quality and meteorological monitors.........

.................................. ............2

3-3. Hourly PM concentrations and wind speeds at the Zuni Hills monitor on

N ovember 4 and 5, 2011................................................................................................... 4 10



# 3 -4. Hourly PM concentrations and wind speeds at the Buckeye monitor on

N ovember 4 and 5, 2011................................................................................................... 4 10



# 3 -5. Hourly PM concentrations at Maricopa County mon itors and visibility at KPHX............ 5 10



# 4- 1. 24-hr average PM concentrations at the Higley monitor (2007–2011)........................... 1 10



# 5-1 . Timeline of Maricopa County fugitive dust rules and ordinances...................................... 5

# Exceptional Event, Phoenix, November 4, 2011 List of Tables



# viii 

# List of Tables

Table Page

2-1. Maricopa County area monitor information and PM measurements on November

4 , 2011. ............................................................................................................................. 4 10



# 3- 1. Observed PM , wind speeds and wind gusts at Phoenix area monitors on

N ovember 4, 2011............................................................................................................. 3 10



# 5-1 . Rules and ordinances regul ating particulate matter emissi ons in Maricopa County......... 2

5-2. Pinal County rules regulating existing and new non-point sources in Pinal County.......... 3

5-3. Pinal County rules regulating fugitive dust in Pinal County portion of Maricopa

County PM Nonattainment Area..................................................................................... 3 10

# Exceptional Event, Phoenix, November 4, 2011 Int roduction



# 1 

# 1. Introduction

On November 4, 2011, 18 air quality monitors in the Phoenix PM 10 

# nonattainment area

recorded 24-hr average PM 10 

# concentrations in excess of the National Ambient Air Quality

Standard (NAAQS) for PM 10 

# of 150 μg/m 3 

# . The purpose of this report is to demonstrate that

these exceedances were due to naturally occurring windblown dust, were not reasonably

controllable or preventable, were historically unusual, and would not have occurred “but-for” the

windblown dust and that they therefore constitute an Exceptional Event as defined by the U.S.

Environmental Protection Agency’s (EPA) Exceptional Events Rule (EER).



# 1.1 Report Contents

Section 2 of this assessment contains a co nceptual model of the wind-blown dust event

that transpired on November 4, 2011, providing a background narrative of the exceptional event

and an overall explanation that the event affected air quality. Section 2 also provides evidence

that the event was a natural event.

Section 3 of this assessment establishes a clear causal connection between the natural

event on November 4, 2011, and the exceedances of the 24-hr PM 10 

# standard at the monitoring

stations. The evidence in this section also c onfirms that the event in question both affected air

quality and was the result of natural events.

Section 4 of this assessment illustrates that the event of November 4, 2011, produced

PM 10 

# concentrations in excess of normal historical fluctuations.

Section 5 of this assessment details the existing dust control measures and

demonstrates that despite the presence and enforcement of these controls, the event of

November 4, 2011, was not reasonably controllable or preventable.

Section 6 of this assessment builds upon the demonstrations made in the previous

sections, showing a clear causal connection be tween the natural event and the exceedances,

and concludes that the exceedances of the 24-hr PM 10 

# standard on November 4, 2011, would

not have occurred “but for” the event.

Appendix A contains time-series graphs and data tables to supplement Section 3.

Appendix B contains links to videos, images, and media reports to supplement Section 3.

Appendix C contains time-series graphs to supplement Section 4. Appendix D contains air

quality forecasts issued by the Arizona Depa rtment of Environmental Quality (ADEQ) and

weather statements and warnings issued by the National Weather Service. Appendix E

contains a copy of the affidavit of public notice concerning this assessment report.



# 1.2 Ex ceptional Event Rule Requirements

In addition to the technical requirements that are contained within the EER, procedural

requirements must also be met in order for the EPA to concur with the flagged air quality

# Exceptional Event, Phoenix, November 4, 2011 Introduction



# 2 

# monitoring data. This section of the report lists the requirements of the EER and associated

guidance and discusses how ADEQ addressed those requirements.



# 1.2.1 Public Notification that the Event Was Occurr ing (40 CFR 50.14(c)(1)(i))

ADEQ issued Dust Control Action Forecasts and Air Quality Forecasts for Maricopa

County advising citizens of the potential for high wind dust events on November 4, 2011. More

information on ADEQ’s forecasts can be found in Section 5.2 of this report. The forecast

products that were issued for November 4, 2011, are included in Appendix D.



# 1.2.2 Place Informal Flag on Data in AQS (40 CFR 50.14(c)(2)(ii))

ADEQ and other operating air quality agencies in Arizona submit data into the EPA’s Air

Quality System (AQS), the official repository of ambient air quality data. This data submittal to

AQS includes particulate matter (PM) data from both filter-based and continuous monitors

operated in Arizona.

When ADEQ and/or another agency operating monitors in Arizona suspect that data

may be influenced by an exceptional event, ADEQ and/or the other operating agency expedites

analysis of the filters collected from the pot entially-affected filter-based air monitoring

instruments, quality-assures the results, and submits the data into AQS. ADEQ and/or other

operating agencies also submit data from continuous monitors into AQS after quality assurance

is complete.

If ADEQ and/or other operating air qualit y agencies have determined that a potential

exists that a monitor’s reading(s) have been influenced by an exceptional event, a preliminary

flag is submitted for the measurement in AQS. The data are not official until they undergo more

thorough quality assurance and quality control, le ading to certification by May 1 of the year

following the calendar year in which the data were collected (40 CFR 58.15(a)(2)). The

presence of the flag on the November 4, 2011, data can be confirmed in AQS.



# 1.2.3 Notify EPA of Intent to Flag Through Submission of Initial Event

Description by July 1 of Calenda r Year Following Event (40 CFR

50.14(c)(2)(iii))

ADEQ submitted notice to EPA on August 29, 2012, listing all days from calendar year

2011 that ADEQ intends to analyze under the Exceptional Events Rule. The PM 10 

# exceedances that occurred on November 4, 2011, in the Phoenix PM 10 

# nonattainment area

were included on this list. This assessment report serves as demonstration supporting the

flagging of these data.



# 1.2.4 Document that the P ublic Comment Process Was Followed for Event

Documentation (40 CFR 50.14(c)(3)(iv))

ADEQ posted this assessment report on the ADEQ webpage and placed a hard copy of

the report in the ADEQ Records Management Center for public review. ADEQ opened a 30-day

public comment period on December 3, 2012. A copy of the public notice certification, along

# Exceptional Event, Phoenix, November 4, 2011 Introduction



# 3 

# with any comments received, will be submitted to EPA, consistent with the requirements of 40

CFR 50.14(c)(3)(iv). See Appendix E for a copy of the affidavit of public notice.



# 1.2.5 Submit Demonstr ation Suppor ting Exception al Event Flag (40 CFR

50.14(a)(1-2))

At the close of the public comment period, and after ADEQ has had the opportunity to

consider any comments submitted on this document, ADEQ will submit this document, the

comments received, and ADEQ’s responses to those comments to EPA Region 9 headquarters

in San Francisco, California. The deadline for the submittal of this package is September 30,

2014.



# 1. 2.6 Documentation Requirements (40 CFR 5 0.14(c)(3)(iii))

The EER states that in order to justify t he exclusion of air quality monitoring data,

evidence must be provided for the following elements:

1. The event satisfies the criteria set forth in 40 CFR 501(j) that

a. the event affected air quality,

b. the event was not reasonably controllable or preventable, and

c. the event was caused by human activity unlikely to recur in a particular

location or was a natural event;

2. There is a clear causal relationship between the measurement(s) under

consideration and the event;

3. The event is associated with a measured concentration(s) in excess of normal

historical fluctuations; and

4. There would have been no exceedance or violation but for the event.

# Exceptional Event, Phoenix, November 4, 2011 C onceptual Model



# 1 

# 2. Conceptual Model

This section provides a narrative background and summarizes the meteorological and

air quality conditions in place on November 4, 2011 in the Phoenix area. Elements described in

this section include

 A description and map of the geographic setting of the air quality and meteorological

monitors.

 A d escription of Phoenix’s climate.

 An overall description of meteorological and air quality conditions on the event day.



# 2.1 Geographic Setting and Monitor Locations

Phoenix is located in the Salt River Valley in so uth-central Arizona. It lies at an elevation

of 1,090 feet above mean sea level (msl) in the northeastern part of the Sonoran Desert. Other

than the mountains in and around the city, the topography of Phoenix is generally flat. The

Phoenix area is surrounded by the McDowell Mountains (~4,200 ft msl) to the northeast, the

foothills of the Bradshaw (~7,900 ft msl) and Mazataal (~7,900 ft msl) ranges to the north, the

White Tank Mountains (~4,500 ft msl) to the west, the Sierra Estrella (~4,450 ft msl) to the

southwest, and the Superstition Mountains (~5,000 ft msl) far to the east. Within the City are

the Phoenix Mountains (~2,600 ft msl) and South Mountain (~2,600 ft msl). Current

development is pushing north, west, and south into Pinal County.

A fairly dense network of air quality and met eorological monitors exists throughout the

Phoenix area, with a much less dense network of monitors throughout the rest of Arizona.

Figure 2-1 shows the general geographic setting of Phoenix, as well as the locations of PM 10 

# monitors that recorded exceedances on November 4, 2011. These monitors include AQS

monitors, which measure air quality and meteorological data, and National Weather Service

(NWS) monitors, which measure meteorological dat a only. Some of the AQS monitors in the

Phoenix area are run by the Maricopa County Air Quality Department (MCAQD), while others

are run by ADEQ. The primary NWS site used in this demonstration package was the Phoenix

Sky Harbor International Airport (KPHX) site, because of that site’s high data quality, data

completeness, and representativeness of meteorological conditions in the Phoenix area.

Figure 2-2 shows the locations of PM 10 

# monitors statewide on November 4, 2011.

Figure 2-3 depicts the drainage systems or watershe ds for the State of Arizona. Many

of the rivers that form Arizon a’s drainage system are dry for most of the year and, consequently,

are sources of silt and fine soils that become suspended and add to regional PM 10 

# loadings

during high wind events. Much of this alluvial matter and fine soil is deposited in the low-lying

areas of central and southern Arizona, with larger depositional areas focused in and around the

confluences of dry river channels.Exceptional Event, Phoenix, November 4, 2011Conceptual Model1Figure 2-1.Locations of air quality monitors that recorded exceedances of the 24-hr PM10NAAQS and NWS monitors in thePhoenix area.

# Exceptional Event, Phoenix, November 4, 2011 Conceptual Model



# 1 Figure 2-2. Location of sites monitoring PM 10 

# in Arizona on November 4, 2011.

# Exceptional Event, Phoenix, November 4, 2011 Conceptual Model



# 2 Figure 2-3. Drainage system of Phoenix, Arizona.

# Exceptional Event, Phoenix, November 4, 2011 Conceptual Model



# 3 

# 2. 2 Climate

Phoenix has an arid climate, with very hot summers and temperate winters. The

average summer high temperatures are among the hottest of any populated area in the United

States ( Figure 2-4 ). Temperatures reach or exceed 100°F an average of 110 days annually,

and reach or exceed 110°F an average of 18 days annually. Phoenix receives an average of

7.66 inches of rain per year. The bulk of this rain usually falls during the December through

March and July through August time periods. During the December through March period,

winter storms originating from the Pacific Ocean can produce significant rains in southwestern

Arizona. During the mid- to late-summer time period, monsoonal moisture originating from the

Gulf of California, Gulf of Mexico, and large thunderstorm complexes over the Sierra Madre

Occidental Mountains in Mexico move northward into Arizona.

0.0 0.2 0.4 0.6 0.8

0 20 40 60 80 1.0 1.2

100 120Precipitation(inches)Temperature(°F)



# Precipitation

Max Temp

Min Temp

Mean Temp



# Figure 2-4. Average monthly temperatures and precipitation for Phoenix, 1981–2010.



# While windblown dust events in Arizona during the summer monsoon season are often

due to outflow winds from thunderstorms, windblown dust events in the fall are usually due to

strong winds associated with low-pressure systems and cold fronts moving southeast across

California and Arizona. These winds are the result of strong surface pressure gradients

between the approaching low-pressure system or cold front and higher pressure ahead of it. As

the low-pressure system (or cold front) a pproaches and passes, gusty southwesterly winds

typically shift to northwesterly. The strong winds can loft dust into the air and transport it over

long distances, especially if soils in the source region are dry.



# 2.3 Event Day Summary

On the afternoon and evening of November 4, 2011, strong winds generated by an

approaching cold front transported dust northeastward into the Phoenix area ( Figure 2-5 ; cold

# Exceptional Event, Phoenix, November 4, 2011 Conceptual Model



# 4 

# front depicted in blue). The windblown dust resulted in 24-hr average PM 10 

# concentrations in

exceedance of the NAAQS at 18 air quality monitors ( Table 2-1 ). The PM 10 

# concentrations

measured at these monitors were in excess of normal historical fluctuations. The dust was

naturally occurring and likely originated over undeveloped lands south of the Phoenix area, and

wind speeds in excess of 20 mph throughout the Phoenix area and over 25 mph at some NWS

stations, with gusts frequently over 35 mph, overwhelmed reasonable dust control measures.

The PM 10 

# monitors with exceedances were located across the Phoenix PM 10 

# nonattainment

area, as well as in Pinal, Pima, and Santa Cruz Counties, illustrating the widespread, regional

nature of this event.



# Phoenix

Figure 2-5. Gusty south-southwesterly winds associated with an approaching cold front

transported dust north-northeastward to the Phoenix area on November 4, 2011.

Table 2-1. Maricopa County area monitor information and PM 10 

# measurements on

November 4, 2011. The exceedance monitors discussed in this report are shown in bold.

Monitor Monitor

Type Operator AQS Monitor ID 24-hr Avg

PM 10 

# (μg/m 3 

# ) 1-hr Max

PM 10 

# (μg/m 3 

# ) Time of

Max 1-hr

PM 10 

# (LST) AQS

Qualifier

Flag

Maricopa County

# Exceptional Event, Phoenix, November 4, 2011 Conceptual Model



# 5 Monitor Monitor

Type Operator AQS Monitor ID 24-hr Avg

PM 10 

# (μg/m 3 

# ) 1-hr Max

PM 10 

# (μg/m 3 

# ) Time of

Max 1-hr

PM 10 

# (LST) AQS

Qualifier

Flag

Buckeye TEOM MC 04-013-4011-81102-1 284 1638 1700 RJ

Central Phoenix TEOM MC 04-013-3002-81102-4 223 1258 1800 RJ

Durango Complex TEOM MC 04-013-9812-81102-1 251 1145 1700 RJ

Dysart TEOM MC 04-013-4010-81102-1 224 1370 1800 RJ

Fort McDowell/Yuma

Frank TEOM FMIR 04-013-5100-8112-1 237 N/A N/A

Glendale TEOM MC 04-013-2001-81102-1 229 1083 1700 RJ

Greenwood TEOM MC 04-013-3010-81102-1 231 1507 1800 RJ

Higley TEOM MC 04-013-4006-81102-1 258 1243 1500 RJ

JLG Supersite BAM ADEQ 04-013-9997-81102-3 200 985

985 1700

1800 RJ

JLG Supersite TEOM ADEQ 04-013-9997-81102-4 199 1346 1800 RJ

North Phoenix TEOM MC 04-013-1004-81102-1 186 N/A N/A RJ

North Phoenix BAM MC 04-013-1004-81102-2 186 1053 1800 RJ

South Phoenix TEOM MC 04-013-4003-81102-1 231 904 1800

West Chandler TEOM MC 04-013-4004-81102-1 670 2745 1500 RJ

West 43 rd 

# Avenue TEOM MC 04-013-4009-81102-1 242 1230 1700 RJ

West Phoenix TEOM MC 04-013-0019-81102-1 279 1506 1700 RJ

Zuni Hills TEOM MC 04-013-4016-81102-1 258 1574 1800 RJ

Apache County

N/A N/A WMAT 04-001-1003-81102-1 29 56 2200

Cocnino County

N/A N/A ADEQ 04-005-1237-81102-1 N/A N/A N/A

Gila County

Hayden Old Jail TEOM ADEQ 04-007-1001-81102-3 119 508 2300 IJ

Navajo County

N/A N/A WMAT 04-017-1002-81102-1 36 63 2100

Pima County

Ajo TEOM ADEQ 04-019-0001-81102-3 149 444 1400 IJ

Geronimo BAM PCDEQ 04-019-1113-81102-1 116 517 2200

Green Valley BAM PCDEQ 04-019-1030-81102-1 62 230 2100

Orange Grove FRM PCDEQ 04-019-0011-81102-2 N/A N/A N/A

Rillito TEOM ADEQ 04-019-0020-81102-3 226 1241 2200 RJ

South Tucson FRM PCDEQ 04-019-1001-81102-1 N/A N/A N/A

Pinal County

Apache Junction

Fire Station TEOM PCAQCD 04-021-3002-81102-3 225 825 1600 RJ

Casa Grande

Downtown TEOM PCAQCD 04-021-0001-81102-3 428 2377 1500 RJ

Combs School TEOM PCAQCD 04-021-3009-81102-3 280 1132 1600 RJ

Cowtown TEOM PCAQCD 04-021-3013-81102-3 395 1326 1500 RJ

# Exceptional Event, Phoenix, November 4, 2011 Conceptual Model



# 6 Monitor Monitor

Type Operator AQS Monitor ID 24-hr Avg

PM 10 

# (μg/m 3 

# ) 1-hr Max

PM 10 

# (μg/m 3 

# ) Time of

Max 1-hr

PM 10 

# (LST) AQS

Qualifier

Flag

Maricopa TEOM PCAQCD 04-021-3010-81102-3 336 1123 1600 RJ

Pinal County Housing TEOM PCAQCD 04-021-3011-81102-3 1161 2404 1400 RJ

Stanfield TEOM PCAQCD 04-021-3008-81102-3 586 1987 1500 RJ

Santa Cruz County

Nogales Post Office BAM ADEQ 04-023-0004-81102-3 151 316 1600 IJ

Yuma County

Yuma Supersite TEOM ADEQ 04-027-8011-81102-3 52 170 1700

TEOM: Tapered element oscillating microbalance monitor

BAM: Beta attenuation monitor

FRM: Federal reference method

WMAT: White Mountain Apache Tribe of Fort Apache Reservation, AZ

MC: Maricopa County Air Quality Department

ADEQ: Arizona Department of Environmental Quality

FMIR: Fort McDowell Indian Reservation

PCAQCD: Pinal County Air Quality Control District

PCDEQ: Pima County Department of Environmental Quality

RJ: qualifier flag for high winds

IJ: qualifier flag for high winds

# Exceptional Event, Phoenix, November 4, 2011 Ca usal Relationship



# 3. Causal Relationship

3.1 Discussion

Meteorological and air quality observations indicate that dust carried by gusty winds

accompanied by an approaching cold front was directly responsible for the high PM 10 

# concentrations observed in the Phoenix area on November 4, 2011. On the afternoon of

November 4, a strong cold front was rapidly moving southeastward across California into

western Arizona ( Figure 3-1 ). A strong surface pressure gradient associated with this front led

to the development of widespread, gusty southwes terly winds across much of Arizona, including

in the Phoenix area. The likely source region for PM 10 

# during the November 4, 2011, event was

the south-central Arizona desert region south of the Phoenix PM 10 

# nonattainment area. This

region largely consists of natural, undisturbed de sert. In addition, the two-month period prior to

November 4, 2011, was very dry in Phoenix, with only 0.08 inches of rain recorded at Phoenix

Sky Harbor International Airport; as a result, soils were very dry. This combination of geography

and lack of rainfall preceding the event resulted in a large fetch of soils that were particularly

vulnerable to particulate suspension.

Figure 3-1. Visible satellite image from 1600 LST on November 4, 2011 (GOES-West),

depicting a strong cold front approaching Arizona. Strong south to southwesterly winds

ahead of this front transported dust into the Phoenix area.

1

# Exceptional Event, Phoenix, November 4, 2011 Causal Relationship



# As the cold front approached Phoenix, winds from the southwest increased and were

gusty for most of the afternoon and evening. Figure 3-2 and Table 3-1 illustrate wind and PM 10 

# data in the Phoenix area during the late afternoon hours of November 4, 2011, when PM 10 

# concentrations were highest. Monitors in the Phoenix area measured sustained winds of over

20 mph and wind gusts in excess of 30 mph coincident with the high PM 10 

# concentrations while

some NWS stations in the Phoenix area measured sustained winds above 25 mph with strong

gusts above 35 mph ( Figures 3-3 and 3-4 , Table 3-1, Appendix A ). These conditions lasted

for several hours, resulting in a prolonged period of dust transport into the Phoenix area.

Visibility at KPHX ( Figure 3-5 ) and other regional airports (Appendix A) also decreased

significantly with the arrival of the dust, prompting the National Weather Service office in

Phoenix, Arizona, to issue a Dust Storm Warning for Maricopa County (see Appendix D). It is

also important to note that winds were lighter and PM 10 

# concentrations were much lower before

the dust storm, illustrating the correlation be tween the high winds and the dust. Visibility

cameras in the Phoenix area also clearly depicted the rapid arrival of dust and the resulting

significant reduction in visibility on the afternoon of November 4, 2011. Links to these videos

and other media coverage and images pertaining to this windblown dust event are shown in

Appendix B.

Figure 3-2. Phoenix area air quality and meteorological monitors. Wind and PM 10 

# data

and time of observation are shown in Table 3-1. Gusty southwesterly winds ahead of an

approaching cold

front transported dust into the Phoenix area on November 4, 2011. Circular symbols and

numbers are placed at the location of the monitor site; wind barbs are offset for visual

clarity.

2

# Exceptional Event, Phoenix, November 4, 2011 Causal Relationship



# Table 3-1. PM 10 

# , wind speeds and wind gusts at Phoenix area monitors on November 4,

2011. Symbols in the first column correspond to monitor locations in Figure 3-2. R R



# Monitor 1-hr Max

PM 10 

# (  g/m 3 

# ) Time of

Observation

(LST) Wind

Speed

(mph) Wind

Gust

(mph) Wind

Direction

(degrees)

Higley 1243 1500 14 32 215

West Chandler 2745 1500 19 36 218

KIWA

- 1547 17 35 220

KGEU

- 1547 21 29 220

KPHX

- 1551 20 27 190

KCHD

- 1654 28 32 210

Buckeye 1638 1700 21 39 217

KDVT

- 1700 21 28 230

Durango

Complex 1145 17:00 13 29 245

Glendale 1083 1700 20 40 233

West 43 rd



# Avenue 1230 1700 16 31 242

West Phoenix 1506 1700 16 33 246

JLG

Supersite(3) 985 1700 9 23 239

KBXK

- 1755 25 36 180

KLUF

- 1757 32 38 220

Central Phoenix 1258 1800 16 33 259

Dysart 1370 1800 14 33 212

Greenwood 1507 1800 14 32 237

JLG

Supersite(4) 1346 1800 11 26 234

North

Phoenix(2) 1053 1800 11 30 240

South Phoenix 904 1800 7 27 255

Zuni Hills 1574 1800 22 37 218 

# 4

13

16 10 9 7

2 5 1 14

2 12 6 4 11

7

6

2

15

5 3 8

3

# Exceptional Event, Phoenix, November 4, 2011 Causal Relationship



# Figure 3-3. Hourly PM 10 

# concentrations and wind speeds at the Zuni Hills monitor on

November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply increased at

1600 LST on November 4, 2011, indicating the arrival of windblown dust. Note that PM 10 

# concentrations were not available at 1200 or 1300 LST on November 4, 2011 or at 0200

LST on November 5, 2011.

Figure 3-4 . Hourly PM 10 

# concentrations and wind speeds at the Buckeye monitor on

November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply increased at

1600 LST on November 4, 2011, indicating the arrival of windblown dust. Sustained

winds were measured over 20 mph with gusts over 35 mph. Note that PM 10 

# concentration data was not available at 0000 LST on November 5, 2011.

4

# Exceptional Event, Phoenix, November 4, 2011 Causal Relationship



# Figure 3-5. Hourly PM 10 

# concentrations at Maricopa County monitors and visibility at

KPHX. Visibility was greatly reduced after 1500 LST on November 4, coinciding with the

sharp increase in PM 10 

# concentrations at Phoenix area monitors, indicating the arrival of

windblown dust.



# Strong, gusty winds continued into the overnight hours as the cold front moved through

the Phoenix area. However, PM 10 

# concentrations decreased after 2000 LST; this drop in PM 10 

# was likely due in part to rain showers. The rain acts to remove suspended PM 10 

# from the

atmosphere and also moistens the surface, ma king the soils less vulnerable to suspension by

the strong winds.



# 3.2 Summary

The information presented in this section demonstrates a clear causal relationship

between the windblown dust and the PM 10 

# exceedances measured in the Phoenix PM 10 

# nonattainment area on November 4, 2011. The wind and PM 10 

# data shown in this section

illustrate the spatial and temporal representation of the dust storm as it moved through Maricopa

County. In addition, the time series plots of air quality and meteorological data found in this

section and in Appendix A show that the sharp increase in PM 10 

# concentrations coincided with

the strong wind speeds and wind gusts, and that the strong winds and high PM 10 

# concentrations

were experienced over a large area.

5

# Exceptional Event, Phoenix, November 4, 2011 Historical Norm



# 4. H istorical Norm

4. 1 Analysis

PM 10 

# concentrations measured at Phoenix-area monitors on November 4, 2011, were

unusual and in excess of normal historical fluctuat ions. To establish the severity of this event,

PM 10 

# concentrations measured on November 4, 2011, were compared to a historical 2007–

2011 5-year annual data set at each monitor ( Figure 4-1 and Appendix C ). The PM 10 

# concentrations measured at the Higley monitor (Figure 4-1) on November 4, 2011, resulted in

one of the highest 24-hr averages measured over the 5-year period. Similar time-series plots

for the other monitors with exceedances of the 24-hour PM 10 

# standard are shown in Appendix

C.

Figure 4-1. 24-hr average PM 10 

# concentrations at the Higley monitor (2007–2011). The

24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and highlighted

by the arrow.



# 4. 2 Summary

Given the recorded values and using a methodology similar to the one accepted by EPA,

it is clear that the PM 10 

# levels on November 4, 2011, were outside normal historical fluctuations.

This analysis provides evidence that the event affected air quality on a historic scale.

# Exceptional Event, Phoenix, November 4, 2011 Historical Norm

# Exceptional Event, Phoenix, November 4, 2011 Not R easonably Controllable or Preventable



# 1 

# 5. Not Reasonably Contro llable or Preventable

5.1 Ba ckground

ADEQ and MCAQD are responsible for implementing regulatory measures to control

emissions from agricultural sources, stationary sources, fugitive dust sources, and open burning

within Maricopa County. Three major programs provide or contribute to air pollution control

measures for the Greater Phoenix area. These programs include

1. AD EQ’s Agricultural Best Management Program (AgBMP)

2. Ma ricopa County’s Inspection and Compliance Program

3. AD EQ’s Air Quality Forecasting Program

Specifically, ADEQ is responsible for co mpliance assistance and enforcement of

Agricultural Best Management Practices developed by the Governor’s Agricultural Best

Management Practices Committee, while MCAQD is responsible for compliance assurance for

all other significant sources of PM 10 

# emissions. In addition to routine inspections and

inspections driven by complaints, inspections are often increased when (1) ADEQ forecasters

issue a Maricopa County Dust Control Forecast of “High Risk”, (2) ADEQ forecasters issue a

High Pollution Advisory, or (3) near-real-time monitoring data indicate unique activity via high

PM concentrations. The forecasting program and inspection/compliance programs work

together so that resources can be best utilized during days of greatest risk for elevated PM

emissions.

On July 25, 2002, EPA took initial action to finalize approval of the Best Available

Control Measure (BACM) and the Most Stringen t Measure (MSM) demonstrations in the Serious

Area PM 10 

# plan for the Maricopa County portion of the metropolitan Phoenix PM 10 

# nonattainment area (67 FR 48718). These BACM and MSM demonstrations were again

approved by EPA on July 14, 2006 (71 FR 43979). The Agricultural Best Management

Practices General Permit rule and related definitions have been adopted into the Arizona

Administrative Code as R18-2-610 and R18-2-6 11, pursuant to Arizona Revised Statutes

§49-457 1



# .



# 5.1 .1 Control Measures

Maricopa County regulations of PM 10 

# emissions are listed in Table 5-1

.

1 

# Updates to the AgBMP program in December, 2011, clarified BMPs for crops and added BMPs for animal

operations. Effective 12/29/2011, R18-2-611 was renumbered to R18-2-610.01 Agricultural PM10 General Permit

for Crop Operations and R18-2-611.01 Animal Operations PM10 General Permit was added. Definitions for Crop

Operations were revised at R18-2-610 and new definitions for Animal Operations were added at R18-2-611.

# Exceptional Event, Phoenix, November 4, 2011 Not Reasonably Controllable or Preventable



# 2 Table 5-1. Rules and ordinances regulating PM emissions in Maricopa County.



# Rule/Ordinance Number & Title Description

Rule 300: Visible emissions Establishes standards for visible emissions and opacity.

Rule 310: Fugitive dust from dustgenerating operations Establishes limits for the emissions of particulate matter into the

ambient air from any property, operations, or activity that may serve as

a fugitive dust source.

Rule 310.01: Fugitive dust from nontraditional sources of fugitive dust Establishes limits for the emissions of particulate matter into the

ambient air from open areas, vacant lots, unpaved parking lots, and

unpaved roadways which are not regulated by Rule 310 and which are

not required to have either a permit or a dust control plan.

Rule 311: Particulate matter from

process industries Establishes emission rates based on process weight applicable to any

affected operations not subject to Rule 316.

Rule 312: Abrasive blasting Establishes limits for particulate emissions from abrasive blasting

operations.

Rule 314: Open outdoor fires and

indoor fireplaces at commercial and

institutional establishments Establishes limits for the emissions of air contaminants produced from

open burning.

Rule 316: Nonmetallic mineral

processing Establishes limits for the emissions of particulate matter into the

ambient air from any nonmetallic mining operation or rock product

processing plant.

Rule 317: Hospital/medical/infectious

waste incinerators Establishes limits for the emissions of air pollutants from medical

waste incinerators.

Rule 322: Power plant operations Establishes limits for the emissions of nitrogen oxides, sulfur oxides,

carbon monoxide, and particulate matter from existing power plants

and cogeneration plants.

Rule 323: Fuel burning equipment

from industrial/commercial/

institutional (ICI) sources Establishes limits for the emissions of nitrogen oxides, sulfur oxides,

carbon monoxide and particulate matter from ICI sources.

Rule 324: Stationary internal

combustion (IC) engines Establishes limits for the emissions of carbon monoxide, nitrogen

oxides, sulfur oxides, volatile organic compounds, and particulate

matter from stationary internal combustion engines, including

stationary IC engines used in cogeneration.

Rule 325: Brick and structural clay

products (BSCP) manufacturing Establishes limits for particulate matter emissions from the use of

tunnel kilns for curing in the BSCP manufacturing processes.

Ordinance P-25: Leaf blower

restriction Establishes restrictions for leaf blowers in incorporated and

unincorporated sections of Area A in Maricopa County.

Ordinance P-26: Residential wood

burning restriction Establishes restrictions for residential wood burning.

Ordinance P-27: Vehicle parking

and use on unstabilized vacant lots Establishes restrictions for vehicle parking and use on unstabilized

vacant lots in unincorporated sections of Area A in Maricopa County.

Ordinance P-28: Off-road vehicle

use in unincorporated areas of

Maricopa County Establishes restrictions for operating vehicles on unpaved property in

unincorporated areas of Maricopa County.

# Exceptional Event, Phoenix, November 4, 2011 Not Reasonably Controllable or Preventable



# 3 

# Rule/Ordinance Number & Title Description

Arizona Administrative Code R18-

2-611 & 610: Agricultural PM 10 

# general permit Establishes a requirement for commercial farmers to implement best

management practices and maintain a record demonstrating

compliance.



# 5.1 .2 Additional Measures

In addition to the rules and regulations listed in Table 5-1 , other PM 10 

# -reducing control

measures (e.g., paving unpaved roads, PM 10 

# -certified street sweepers, controlling unpaved

parking lots, etc.) have been committed to and implemented by local jurisdictions throughout the

PM 10 

# nonattainment area and incorporated into the Arizona state implementation plan (SIP)

through PM 10 

# plans such as the Revised Maricopa Association of Governments’ (MAG) 1999

Serious Area Particulate Plan for PM 10 

# for the Maricopa County Nonattainment Area. The Pinal

County Air Quality Control District (PCAQCD) al so implements regulatory control measures on

emissions from existing and new non-point sources within Pinal County (see Table 5-2 ).

Additionally, the PCAQCD implements specific nonattainment rules for that part of the Phoenix

PM 10 

# nonattainment area that resides in Pinal County (see Table 5-3 ).

Table 5-2. Pinal County rules regulating existing and new non-point sources in Pinal County.



# Article Number & Title Description

Article 2: Fugitive dust Provides a mechanism to reasonably regulate operations which

periodically may cause fugitive dust emissions into the atmosphere.

Article 3: Construction sites –

fugitive dust Improves the control of excessive fugitive dust emissions that have

been traditionally associated with construction, earthwork, and land

development, and thereby minimize nuisance impacts.

Table 5-3. Pinal County rules regulating fugitive dust in Pinal County portion of the

Phoenix PM 10 

# Nonattainment Area.



# Article Number & Title Description

Article 4: Nonattainment area rules;

dustproofing for commercial parking,

drives, and yards Establishes rules to avoid violations of the prevailing PM 10 

# standard

and additionally minimize nuisance impacts by improving control of

excessive fugitive dust emissions from unpaved parking lots.

Article 5: Nonattainment area rules;

stabilization for residential parking

and drives Establishes rules for stabilizing residential properties.

Article 6: Restrictions on vehicle

parking and use on vacant lots Establishes rules for unpaved or unstable vacant lots.

Article 7: Construction sites in

nonattainment areas – fugitive dust Establishes rules to avoid violations of the prevailing PM 10 

# standard

and additionally minimize nuisance impacts by improving control of

excessive fugitive dust emissions from activities associated with

construction, earthwork, or land development.

# Exceptional Event, Phoenix, November 4, 2011 Not Reasonably Controllable or Preventable



# 4 

# Articl e Number & Title Description

Article 8: Nonattainment area rules,

requirement for stabilization of

disturbed areas at vacant lots Establishes rules for stabilizing disturbed areas at vacant lots.



# 5.1 .3 PM 10 

# Rule Effectiveness

MCAQD analyzed the effectiveness of its fugitive dust rules (Rules 310, 310.01 and 316)

in terms of permit compliance rates. This rule effectiveness (RE) study was designed to assess

how many sources regulated by MCAQD during the subject time period received no PM 10 

# emissions-related violations. As a basis for comparison, the percentage of permitted sources in

compliance during calendar year 2007 was 76% for sources subject to Rule 310, 85% for Rule

310.01 sources, and 40% for Rule 316 sources. In early 2008, Rules 310, 310.01, and 316

were strengthened, and new ordinances (covering additional source categories such as leaf

blowers, vacant lots, and off-road vehicles) were adopted. These enhancements resulted from

MCAQD department’s obligations under such agreements as the 2005 Revised PM 10 

# State

Implementation Plan for the Salt River Area and the Maricopa Association of Governments 2007

Five Percent Plan for PM 10 

# for the Maricopa County Nonattainment Area to reduce PM 10 

# emissions throughout the county. Three major areas that contributed to increased compliance

were an increase in departmental staffing (especia lly inspectors), a robust training program, and

regulatory changes that broadened and strengt hened control measures under Rules 310,

310.01, and 316.

Source compliance rates were re-assessed for FY 2009 (July 2008–June 2009), a

period that allowed time for the new and revised regulations to take effect. The results showed

significant increases in compliance compared with the earlier period: to 90% (from 76%) for

Rule 310 sources, 95% compliance (from 85%) for Rule 310.01 sources, and 65% (from 40%)

for Rule 316 sources. These improvements continued into calendar year 2010 with compliance

rates of 94% for Rule 310 sources, 96% for Rule 310.01 sources, and 73% for Rule 316

sources. The timeline below ( Figure 5-1 ) illustrates the improvements in RE over the last

several years; it also points out significant revisions to previous rules, as well as newly adopted

rules and ordinances.

# Exceptional Event, Phoenix, November 4, 2011 Not Reasonably Controllable or Preventable



# 5 Figure 5-1. Timeline of Maricopa County fugitive dust rules and ordinances.



# 5. 1.4 Compliance and Enforcement Activities

MCAQD is prepared to proactively respond to high wind events and protect human

health and well-being. MCAQD ‘s approach consists of two primary components: proactive

inspections conducted routinely, as well as su rveillance inspections conducted during and after

significant air quality events. MCAQD routi nely inspects dust control-permitted sites and

increases the frequency of inspections for permits covering areas of 10 acres or more. Rule

316 sources are also regularly inspected multiple times every year. Maricopa County responds

to the majority of complaints within 24 hours.

Maricopa County monitors the ADEQ Five-Day Dust Control Forecast to identify the

potential for elevated PM 10 

# pollution levels due to high winds or stagnant conditions. When a

High Pollution Advisory (HPA) is issued for Maricopa County, MCAQD conducts increased

surveillance before, during, and after the fore cast event(s). MCAQD also conducts event

surveillance and post-event activities during exceedance days that had not been forecast (i.e.,

those instances in which an HPA had not been issued).

Pre-event surveillance consists of surveying high-risk areas for any dust-generating

activities, educating sources of the impending HPA event, and issuing violations for failure to

comply with local, state, or federal regulations. During the event, MCAQD inspectors survey

high-risk areas to confirm that control measures are in place, document any violations, and

contact other regulatory agencies if necessary. Post-event activities include continued surveys

of high-risk areas, re-inspecting sources that had incurred violations within two business days,

and an internal MCAQD debriefing of event activities.

During 2011, a total of 14 MCAQD air monitoring sites were upgraded with new

equipment that allows the monitoring sites to automatically report measured readings at

5-minute intervals. Previously, only hourly readings were available. The real-time data

reporting system includes a mechanism to alert MCAQD field staff when PM concentrations are

elevated. The system allows MCAQD responders to review concentrations at the monitors and

# Exceptional Event, Phoenix, November 4, 2011 Not Reasonably Controllable or Preventable



# 6 

# to consult the National Weather Service website to check for weather event activity. This

capability allows the MCAQD responder to identify regional events and monitor specific issues.

If necessary, the MCAQD responders can inform nearby stakeholders and local governments of

the elevated PM 10 

# concentraitons.



# 5.1 .5 Review of Source-Permitted Inspections and Public Complaints

ADEQ’s Arizona Unified Repository for In formation Tracking of the Environment

(AZURITE) database was queried to compile a list of inspections for the permitted sources in

the Maricopa area around the time of the November 4, 2011, PM 10 

# exceedances. An evaluation

of all inspection reports, air quality complain ts, compliance reports, and other documentation did

not indicate any evidence of unusual anthropogenic-based PM 10 

# emissions. During the period

of November 1 through November 7, 2011, MCAQD inspectors conducted a total of 146

inspections of permitted facilities, of which 91 were at fugitive dust sources. Additionally,

MCAQD conducted 209 inspections on vacant lots and unpaved parking lots. During this 7-day

period, a total of 18 violations were issued countywide for PM 10 

# and non-PM 10 

# related violations.

Nine violations were issued for PM 10 

# emissions within a 4-mile radius of an exceeding monitor

(Buckeye, Central Phoenix, Higley, and Zuni Hills).

On November 2, 2011, two violations were issued to a permitted facility within 4 miles of

the Buckeye monitor. A violation was issued fo r failure to maintain records of daily selfinspection and implementation of control measur es from the Dust Control Plan. A second

violation was issued for failure to provide to the inspector, in a timely manner, operational

records required in the permit pertaining to grain loading and unloading. The source corrected

the violations on subsequent inspections. The per mitted site is located approximately 1.8 miles

northeast of the Buckeye monitor. During the exceptional event on November 4, 2011, winds

were generally from the southwest at the Buckeye monitor.

On November 3, 2011, a violation was issued to a permitted construction site for failure

to maintain records of daily self-inspection and implementation of control measures in the Dust

Control Plan. At the time of the inspection, no disturbed surfaces were observed, and the

source was complying with the required control measures detailed in their earthmoving permit.

The source corrected the violation and maintained compliance with their permit on subsequent

inspections. The site is approximately 1.4 mile s southeast of the Central Phoenix monitor.

During the exceptional event, the winds were generally from the west and southwest at the

Central Phoenix monitor.

On November 4, 2011, three violations were issued to a permitted construction site

within 4 miles of the Higley monitor. A violation was issued for approximately 0.22 acres of

disturbed area on which no earthmoving activity was occurring. A second violation was issued

for failure to keep dust control records. A third violation was issued for exceeding the permitted

earthmoving area by approximately 0.11 acres. The inspector observed the stability issue at

1210 LST and remained onsite until the entire site was stabilized with water at 1330 LST. The

Higley monitor began showing exceedances at about 1500 LST. The site was permitted for

0.96 acres and observed with 0.22 acres of unstable surface areas. The permitted site is

approximately 1.0 mile north of the Higley monitor. During the exceptional event, the winds

were generally from the south and southwest at the Higley monitor.

# Exceptional Event, Phoenix, November 4, 2011 Not Reasonably Controllable or Preventable



# 7 

# MCAQD was prepared for any complaints received due to the high wind event. During

the 7-day period from November 1 through November 7, 2011, MCAQD received 41 complaints,

of which 30 were related to windblown dust. Each complaint was assigned to, and investigated

by, a MCAQD inspector. A review of all pertinent records from this period indicates that

MCAQD inspectors observed three PM 10 

# emissions violations of local, state, or federal

regulations within a 4-mile radius of exceeding monitors (Zuni Hills and Higley).

On November 2, 2011, a complaint investigation led to the issuance of a violation to the

owner of a vacant lot for failure to stabilize surface areas that had been disturbed by vehicular

activity during a temporary carnival. The vacant lot is approximately 1.5 miles northeast of the

Zuni Hills monitor, and the total disturbed surface area was 0.79 acres. The violation was

observed at 0700 LST, and a City of Peoria water truck began applying water to the unstable

areas at approximately 0915 LST. Additionally, a response letter from the parcel owner

indicated that 3/8-inch gravel had been applied to the property and “No Trespassing” signs were

posted. The vacant lot was stabilized prior to the November 4 high wind event.

On November 4, 2011, a complaint investigation led to the issuance of a violation to the

owner of a vacant lot for failure to stabilize surface areas that had been disturbed by vehicular

activity. The total unstable area was approximately 0.14 acres. The vacant lot is approximately

1.5 miles northeast of the Zuni Hills monitor. During the exceptional event, the winds were

generally from the southwest at the Zuni Hills monitor.

On November 4, 2011, a complaint investigation led to the issuance of a violation to the

owner of a vacant lot for failure to prevent vehicle access. The inspector stated that there was a

small area, approximately 0.01 acres, of unstable soil of caused by foot traffic, bicycles, and

vehicle use. The vacant lot was stabilized with water, while fences, “no access” signs, and nonerodible materials were installed to further control and stabilize the vacant lot. The vacant lot is

approximately 3.3 miles northeast of the Higley monitor. During the exceptional event, the

winds were generally from the south an d southwest at the Higley monitor.

In addition to MCAQD’s efforts in pre- event surveillance and pr oactive inspections,

ADEQ’s Agricultural Best Management Practice Program (Ag BMP) inspector also monitors the

ADEQ Five-Day Dust Control Forecast and the MCAQD air monitoring sites that include realtime data. The ADEQ Ag BMP inspector uses specific knowledge of seasonal activities and

associations with the local growers and dairymen to communicate the importance of limiting

dust-generating activities, especially during high wind events. Additional outreach is conducted

with facility representatives prior to forecast high wind alert days. Should the PM 10 

# readings at

a MCAQD air monitoring site show a notable increase, the ADEQ Ag BMP inspector is

dispatched to contact the owners and operators of agricultural fields in the area to discern

whether their activities are causing negative impacts. The Ag BMP inspector is prepared to

respond to most agriculture complaints within 24 hours.

A review of the inspection reports and site visit documentation shows no evidence to

suggest that agricultural activities produced unusual PM 10 

# emissions. From November 3

through November 4, 2011, the ADEQ Ag BMP inspector distributed notification of the

November 4 PM 10 

# HPA to 12 agricultural operations and conducted surveillance near the

Buckeye monitor on November 4.

# Exceptional Event, Phoenix, November 4, 2011 Not Reasonably Controllable or Preventable



# 8 

# 5 .2 Forecasts and Warnings

Dust forecasts and statements were released prior to the event by both ADEQ and the

NWS office in Phoenix (Appendix D). For November 3, 2011, ADEQ issued a Maricopa County

Dust Control Forecast indicating a high risk level for unhealthy PM 10 

# . The Dust Control

Forecast also indicated a potential for strong and gusty winds throughout the area, as well as

dense blowing and transported dust generated by a very strong trough of low pressure. ADEQ

also issued a PM 10 

# High Pollution Advisory for Maricopa County for November 4, 2011.

The NWS in Phoenix issued a Special Weather Statement on Wednesday, November 2,

2011, indicating that strong winds and blowing dust and sand would be possible on Friday,

November 4. On Thursday, November 3, the NWS issued a Wind Advisory and Blowing Dust

Advisory for the Phoenix area effective 1100 to 2000 LST on Friday, November 4, for the

potential for sustained southerly winds of 25 to 35 mph with gusts to 50 mph and blowing dust

with visibilities reduced to under 1 mile. This time period corresponds to the period of very high

PM 10 

# concentrations reported at Phoenix-area monitors. At 1407 LST on Friday, November 3,

the NWS upgraded the Blowing Dust Advisory to a Dust Storm Warning. NWS offices in

Tucson and Flagstaff, Arizona, and in Las Vegas, Nevada, also issued statements and/or

advisories related to strong winds and blowing dus t, illustrating the widespread, regional nature

of this event.



# 5 .3 Wind Observations

Wind data during the event (Table 3-1, Figure 3-3 and Appendix A) showed several

hours of sustained wind speeds of over 20 m ph, a few NWS sites with peak sustained winds

over 25 and as high as 32 mph, and wind gusts frequently over 35 mph coincident with the high

PM 10 

# concentrations.



# 5.4 Summary

On November 4, 2011, strong winds associat ed with a cold front transported dust and

PM 10 

# into the Phoenix PM 10 

# nonattainment area. The source region of the dust that caused the

exceedances was largely outside the Phoenix PM 10 

# nonattainment area, primarily the deserts

south of the Phoenix PM 10 

# nonattainment area. The Phoenix area is designated as a serious

nonattainment area for PM 10 

# and is required to have BACM for all significant sources of PM 10



# . BACM-approved control measures on significant anthropogenic sources were in place and

enforced during the events, and proactive tracking and response to the events by regulatory

agencies and local governments confirmed the unc ontrollable nature of the dust emissions;

therefore, these previously approved required controls are adequate for meeting the

requirements of an exceptional event and should be considered “reasonable” for these

purposes.

Despite the deployment of comprehensive co ntrol measures and sophisticated response

programs, high wind conditions associated with the approaching cold front transported high

concentrations of PM 10 

# into, and also overwhelmed controls within, the Phoenix PM 10 

# nonattainment area. Widespread sustained winds in excess of 20 mph with some sustained

# Exceptional Event, Phoenix, November 4, 2011 Not Reasonably Controllable or Preventable



# 9 

# winds as high as 32 mph and gusts frequently over 35 mph were strong enough to overwhelm

available efforts to limit PM 10 

# concentrations during the event. The fact that these were natural

events involving strong winds that transported PM 10 

# emissions into and across Maricopa

County, with a majority of the PM 10 

# emissions recorded by Maricopa County area monitors

coming from sources outside of the Phoenix PM 10 

# nonattainment area, provides strong

evidence that the exceedances of November 4, 2011, recorded within the Phoenix PM 10 

# nonattainment area were not reasonably controllable or preventable.

# Exceptional Event, Phoenix, November 4, 2011 B ut-For Analysis



# 1 

# 6. But-For Analysis

6. 1 Discussion

Section 50.14(c)(3)(iv)(D) in 40 CFR Part 50 requires that an exceptional event

demonstration satisfy the condition that “[t]her e would have been no exce edance or violation but

for the event.” The prior sections of this submittal have provided detailed information that, in

regard to the PM 10 

# exceedances at Phoenix area monitors on November 4, 2011,

 t he exceedance was not reasonably controllable or preventable, and

 t here was a clear causal relationship between PM 10 

# transported strong winds originating

in desert areas outside the Phoenix PM 10 

# nonattainment area and the measured PM 10



# exceedances in the Phoenix PM 10 

# nonattainment area.

The weight of evidence in these sections demo nstrates that, but for the existence of dust

emissions generated by strong winds and the associated transport of PM 10 

# , there would have

been no exceedance of the NAAQS for 24-hr average PM 10



# .

As shown in Section 3, maps and time-series plots of PM 10 

# and wind speeds establish a

clear causal relationship between the arrival of strong winds associated with an approaching

cold front and elevated PM 10 

# concentrations at Phoenix-area monitors. Multiple independent

measurements of wind speed, wind direction, and visibility point to the presence of widespread,

strong winds as the mechanism for transport of PM 10 

# into the Phoenix nonattainment area. In

addition, PM 10 

# concentrations were well below the NAAQS on days immediately before and

after the windblown dust event. The source region for the PM 10 

# is clearly identified as desert

areas south of the Phoenix PM 10 

# nonattainment area. The weight of evidence presented in this

submittal provides no alternative that could tie the exceedance of November 4, 2011 to any

causal source except PM 10 

# transported by strong winds, confirming that there would have been

no exceedance but for the presence of this uncontrollable natural event.

As detailed in Section 5, all reasonable control measures were in place and/or

implemented on a continual basis. Air quality-related inspection and compliance data revealed

no violations or complaints within three days before and after the time of the event. Local

regulatory agencies, industry, and the general public were alerted to the possibility of dust

storms due to strong winds via daily forecasts and media reports.



# 6 .2 Summary

The weight of evidence presented in this submittal provides no alternative that could tie

the exceedance of November 4, 2011, to any causal source other than PM 10 

# transported by

strong winds associated with an approaching cold front, confirming that there would have been

no exceedance but for the presence of this uncontrollable natural event.

# Exceptional Event, Phoenix, November 4, 2011 C onclusions



# 1 

# 7. Conclusions

The PM 10 

# exceedances that occurred on November 4, 2011, satisfy the criteria of the

EER, which states that in order to justify the exclusion of air quality monitoring data, evidence

must be provided for the following elements:

 Th e event satisfies the criteria set forth in 40 CFR 501 (j) that

a. t he event affected air quality,

b. t he event was not reasonably controllable or preventable, and

c. the event was caused by human activity unlikely to recur in a particular location or

was a natural event;

 There is a clear causal relationship between the measurement(s) under consideration

and the event;

 The event is associated with a measured concentration(s) in excess of normal historical

fluctuations; and

 There would have been no exceedance or violation but for the event.



# 7 .1 Affects Air Quality

As stated in the preamble to the EER, the event in question is considered to have

affected air quality if it can be shown that there is a clear causal relationship between the

monitored exceedances and the event, and that the event is associated with a measured

concentration in excess of normal historical fluctuations. Given the information presented in

Sections 2, 3, 4, and 5, we can reasonably conclude that the event in question affected air

quality.



# 7 .2 Not Reasonably Controllable or Preventable

Section 50.1(j) of 40 CFR Part 50 requires that an event must be “not reasonably

controllable or preventable” in order to be defined as an exceptional event. This requirement is

met by demonstrating that despite reasonable control measures in place within Maricopa

County, high winds overwhelmed all reasonabl y available controls (Section 5). The PM 10 

# exceedances discussed in this report were caused by naturally occurring strong winds

associated with an approaching cold front that transported dust into the Phoenix area from

areas largely outside the Phoenix PM 10 

# nonattainment area. These facts provide strong

evidence that the PM 10 

# exceedances on November 4, 2011, were not reasonably controllable or

preventable.



# 7.3 Natural Event

As discussed above, the PM 10 

# exceedances in the Phoenix area on November 4, 2011,

were shown to be caused by transport of PM 10 

# into the Phoenix area from widespread strong

winds associated with an approaching cold front. The event therefore qualifies as a natural

event.

# Exceptional Event, Phoenix, November 4, 2011 Conclusions



# 7.4 Clear Causal Relationship

The following points demonstrate that the high PM 10 

# concentrations were caused by

windblown dust:

 Time-serie s of PM 10 

# concentrations show that the timing of high PM 10 

# at Phoenix area

monitors was consistent with gusty winds and low visibilities at Phoenix-area

meteorological stations (Section 3).

 High PM 10 

# concentrations and gusty winds were reported throughout the Phoenix

metropolitan area, as well as across much of Arizona, southeastern California, and

southern Nevada, illustrating the widespread, regional, and uncontrollable nature of this

event (Sections 3 and 5).

 PM 10 

# co ncentrations were well below the NAAQS on days immediately before and after

the windblown dust event (Section 3).

 Dry condit ions preceding the event resulted in soils that were particularly susceptible to

particulate suspension by high winds (Section 3).

 Visibility cameras clearly illust rate the arrival of dust and sign ificant reductions in visibility

in the Phoenix area coinciding with the sharp increases in PM 10 

# concentrations.



# 7 .5 Historical Norm

The 24-hr average PM 10 

# values measured at Phoenix area monitors were historically

unusual compared to a multi-year data set (Section 4).



# 7 .6 But For

On the basis of the weight of evidence described above and in Section 6, the

exceedances of the federal 24-hr PM 10 

# standard on November 4, 2011, in the Phoenix PM 10 

# nonattainment area would not have occurred but for the high winds and transport of dust from

areas largely outside the Phoenix PM 10 

# nonattainment area.

2

# Exceptional Event, Phoenix, November 4, 2011 Appendix A



# A ppendix A:

Air Quality and Meteorological Da ta for Maricopa County

This section contains time-series of PM 10 

# concentrations and wind data for Phoenix-area

air quality monitors on November 4 and 5, 2011. The data show a region-wide increase in wind

speeds and wind gusts coincident with the arrival of dust and high PM 10 

# concentrations.

Figure A-1. Hourly PM 10 

# concentrations and wind speeds at the Central Phoenix

monitor on November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply

increased at 1600 LST on November 4, 2011, indicating the arrival of windblown dust.

1

# Exceptional Event, Phoenix, November 4, 2011 Appendix A



# Figure A-2. Hourly PM 10 

# concentrations and wind speeds at the Durango Complex

monitor on November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply

increased at 1600 LST on November 4, 2011, indicating the arrival of windblown dust.

2

# Exceptional Event, Phoenix, November 4, 2011 Appendix A



# Fi gure A-3. Hourly PM 10 

# concentrations and wind speeds at the Dysart monitor on

November 4 and 5, 2011. PM R R



# 10 

# concentrations and wind speeds sharply increased at

1600 LST on November 4, 2011, indicating the arrival of windblown dust. Note that wind

speed and wind gust data were not available at 0800 LST on November 4, 2011 at the

Dysart monitor.

Figure A-4. Hourly PM 10 

# concentrations and wind speeds at the Glendale monitor on

November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply increased at

1600 LST on November 4, 2011, indicating the arrival of windblown dust. Note that PM 10 

# concentrations were not available at 1200 or 2300 LST on November 4, 2011 or for the

entirety of November 5, 2011 at the Glendale monitor.

3

# Exceptional Event, Phoenix, November 4, 2011 Appendix A



# Figure A-5. Hourly PM 10 

# concentrations and wind speeds at the Greenwood monitor on

November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply increased at

1600 LST on November 4, 2011, indicating the arrival of windblown dust.

Figure A-6. Hourly PM 10 

# concentrations and wind speeds at the Higley monitor on

November 4 and 5, 2011. Note that PM 10 

# concentrations were not available between

1200 and 1400 LST on November 4, 2011 at the Higley monitor.

4

# Exceptional Event, Phoenix, November 4, 2011 Appendix A



# Figure A-7. Hourly PM 10 

# concentrations and wind speeds at the JLG Supersite(3)

monitor on November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply

increased at 1600 LST on November 4, 2011, indicating the arrival of windblown dust.

Figure A-8. Hourly PM 10 

# concentrations and wind speeds at the JLG Supersite(4)

monitor on November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply

increased at 1600 LST on November 4, 2011, indicating the arrival of windblown dust.

5

# Exceptional Event, Phoenix, November 4, 2011 Appendix A



# Figure A-9. Hourly PM 10 

# concentrations and wind speeds at the North Phoenix(2)

monitor on November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply

increased at 1600 LST on November 4, 2011, indicating the arrival of windblown dust.

Figure A-10. Hourly PM 10 

# concentrations and wind speeds at the South Phoenix monitor

on November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply increased at

1600 LST on November 4, 2011, indicating the arrival of windblown dust. Note that PM 10 

# concentrations were not available between 0200 or 0700 LST on November 4, 2011 or at

0000 LST on November 5, 2011 at the South Phoenix monitor.

6

# Exceptional Event, Phoenix, November 4, 2011 Appendix A



# Figure A-11. Hourly PM 10 

# concentrations and wind speeds at the West 43rd Avenue

monitor on November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply

increased at 1600 LST on November 4, 2011, indicating the arrival of windblown dust.

Figure A-12. Hourly PM 10 

# concentrations and wind speeds at the West Chandler

monitor on November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply

increased at 1400 LST on November 4, 2011, indicating the arrival of windblown dust.

Note that PM 10 

# concentration data was not available at 0100 LST on November 5, 2011

at the West Chandler monitor.

7

# Exceptional Event, Phoenix, November 4, 2011 Appendix A



# 8 Figure A-13. Hourly PM 10 

# concentrations and wind speeds at the West Phoenix monitor

on November 4 and 5, 2011. PM 10 

# concentrations and wind speeds sharply increased at

1500 LST on November 4, 2011, indicating the arrival of windblown dust.

# 9U.S. Department of CommerceNational Oceanic &Atmospheric AdministrationQUALITY CONTROLLED LOCAL CLIMATOLOGICAL DATAPHOENIX SKY HARBOR INTL AIRPORT (23183)PHOENIX, AZ (11/2011)National Climatic Data CenterFederal Building151 Patton AvenueAsheville, North Carolina 28801Elevation:1107 ft. above sea levelLatitude:33.427Longitude:-112.003Data Version:VER3DryBulbTempWetBulbTempDewPointTempDateTime(LST)StationTypeSkyConditionsVisibility(SM)WeatherType(F)(C)(F)(C)(F)(C)RelHumd%WindSpeed(MPH)WindDirWindGusts(MPH)StationPressure(in. hg)PressTendNet3-hrChg(mb)SeaLevelPressure(in. hg)ReportTypePrecip.Total(in)Altimeter(in. hg)12345678910111213141516171819202122230404040404040404040404040404040404040404040404040404040404040404040404005101510251035104510551065107510851095110511151125113511444145115511649165117101751184918511900195120512151220022512314231723232330234323511111111111111111111111111111111111111111111111111111111111111111111111SCT180 BKN230SCT180 BKN230SCT180 BKN230SCT170 BKN230SCT170 BKN210SCT160 BKN210FEW180 BKN220 BKN240FEW170 BKN200 BKN240FEW170 BKN200 BKN240FEW170 BKN220 BKN250FEW170 BKN220 BKN250FEW190 BKN220 BKN250FEW110 BKN220 BKN250FEW110 SCT220FEW033 SCT110 SCT220FEW037 SCT110 SCT220FEW039 SCT110 SCT220FEW027 SCT110 SCT220SCT027 SCT110 SCT220SCT027 SCT110 SCT220SCT032 SCT110 SCT220BKN027 BKN065BKN027 BKN065BKN030 BKN065BKN060 BKN095BKN050 OVC065SCT048 BKN060 BKN095SCT048 SCT060 BKN090SCT040 SCT055 BKN090SCT031 BKN060 OVC090FEW031CB BKN075 OVC090FEW031CB BKN075 OVC090FEW031CB BKN075 OVC090FEW031CB BKN043 OVC070FEW031CB BKN043 OVC07010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.007.002.502.504.006.004.004.005.009.008.009.0010.0010.001.751.252.507.003.004.00BLDUBLDUBLDUBLDUBLDUBLDUBLDU-RA-RA-RA-RA+TSRA-TSRA-TSRA-RA BR-RA BR666464646462616667707377798381808175767775727170706662636257555757545418.917.817.817.817.816.716.118.919.421.122.825.026.128.327.026.727.224.024.425.023.922.021.721.021.118.916.717.016.714.013.014.014.012.012.249484847464646474950515354575656576161595958585857585758585453555553539.28.78.78.47.87.97.98.49.29.710.511.612.313.713.213.013.616.316.215.014.814.614.414.214.014.414.114.314.412.311.812.912.911.611.62929292723272924272626272932323234525145464848484752545455525254545252-1.7-1.7-1.7-2.8-5.0-2.8-1.7-4.4-2.8-3.3-3.3-2.8-1.70.00.00.01.111.0s10.67.07.89.08.99.08.311.112.212.012.811.011.012.012.011.011.1252727252126302022191716161617171845423236434446446175737883909090939331078776103891191413142015141614151817151114117292320162522060100130060110080120140110140130160150170240270190260240210250250260240240250200210VR21021020021027027018232625282828262023616133403228.6628.6428.6428.6328.6228.6228.6228.6228.6328.6228.6128.5728.5228.4728.4428.4328.4328.4328.4328.4328.4328.4528.4528.4528.4528.4628.4528.4528.4328.4328.4328.4328.4328.4528.458808850801300700000404600100600529.7929.7729.7729.7629.7529.7529.7529.7529.7629.7629.7429.7029.6529.59M29.5629.56M29.56M29.56M29.58M29.5829.5929.59M29.57MMMMM29.58AAAAAAAAAAAAAAAAAAAAAAAAAAAASPAAAASPAASPAASPAASPAAAAAASPAASPSPSPSPSPAA0.01TT0.2429.8329.8129.8129.8029.7929.7929.7929.7929.8029.7929.7829.7429.6929.6429.6129.6029.6029.6029.6029.6029.6029.6229.6229.6229.6229.6329.6229.6229.6029.6029.6029.6029.6029.6229.62Figure A-14.Quality controlled local climatological data hourly observations table for Phoenix Sky Harbor International Airport, Phoenix,Arizona (11/04/2011). Note in the Weather Type column that BLDU (blowing dust) was reported for several hours. For a more detailedexplanation of the weather codes shown in the table above, please seehttp://www.nws.noaa.gov/oso/oso1/oso12/document/guide.shtml. Datadynamically generated viahttp://cdo.ncdc.noaa.gov/qclcd/QCLCD.

# 10U.S. Department of CommerceNational Oceanic & Atmospheric AdministrationQUALITY CONTROLLED LOCALCLIMATOLOGICAL DATA (final)HOURLY OBSERVATIONS TABLEPHOENIX DEER VALLEY ARPT (03184)PHOENIX, AZ (11/2011)National Climatic Data CenterFederal Building151 Patton AvenueAsheville, North Carolina 28801Elevation: 1455 ft.above sea levelLatitude: 33.688Longitude: -112.081Data Version: VER2DryBulbTempWetBulbTempDewPointTempDateTime(LST)StationTypeSkyConditionsVisibility(SM)WeatherType(F)(C)(F)(C)(F)(C)RelHumd%WindSpeed(MPH)WindDirWindGusts(MPH)StationPressure(in. hg)PressTendNet3-hrChg(mb)SeaLevelPressure(in. hg)ReportTypePrecip.Total(in)Altimeter(in. hg)12345678910111213141516171819202122230404040404040404040404040404040404040404040404040404040404040404005301530253035304530553065307530853095310531153125313531453155316461653170017431751175318291853193319532053215322532325234023531212121212121212121212121212121212121212121212121212121212121212CLRCLRCLRCLRCLRCLRCLRCLRCLRCLRCLRCLRCLRCLRCLRCLROVC029OVC029OVC029OVC029OVC031OVC031OVC029OVC027SCT025 BKN075 OVC095FEW060 BKN095BKN048 BKN055 OVC085BKN050 OVC070BKN041 BKN048 OVC055FEW018 BKN048 OVC070FEW019 BKN039 OVC070SCT012 BKN024 OVC06010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.003.003.002.504.004.004.003.004.006.006.0010.0010.005.006.008.007.00HZHZHZHZHZHZHZHZHZHZ-RA-RA-RA BRVCTS -RA-RA-RA626158566059636466687273757677777372727070696667666662585655555416.716.114.413.315.615.017.217.818.920.022.222.823.924.425.025.023.022.222.021.021.020.619.019.419.018.916.714.413.313.013.012.244444241444445464748505153535456606059585757565655565555545351526.76.55.75.16.56.47.37.68.28.910.010.411.511.712.013.215.315.415.114.213.713.713.313.312.813.012.612.812.111.810.711.02020202022232222232425263030303750515048464748474647495352524850-6.7-6.7-6.7-6.7-5.6-5.0-5.6-5.6-5.0-4.4-3.9-3.3-1.1-1.1-1.12.810.010.610.09.08.08.39.08.38.08.39.411.711.111.09.010.0202023252325212019191717191818244448464642465249495163848790778633056811141089911511172218212022181720181621614182118100090000090080110130140140130140180170160260230240220230230240240240230220220240200200200210240182530292829323229293123332330292928.2828.2728.2628.2528.2428.2328.2328.2328.2528.2528.2228.2028.1528.1028.0728.0628.0628.0528.0528.0628.0628.0528.0728.0828.0928.0928.0928.0828.0528.0528.0628.076658863801300800300304201701201229.7929.7829.7729.7629.7529.7529.7429.7529.7629.7629.7329.7029.6529.6029.5729.56M29.55MMM29.56M29.59M29.5929.5929.5929.55MM29.57AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAASPAASPSPSPAASPAASPAAAAAAAASPSPAAT0.030.060.0829.8429.8329.8229.8129.8029.7929.7929.7929.8129.8129.7829.7529.7029.6529.6229.6129.6129.6029.6029.6129.6129.6029.6229.6329.6429.6429.6429.6329.6029.6029.6129.62Figure A-15.Quality controlled local climatological data hourly observations table for Phoenix Deer Valley Airport, Phoenix, Arizona(11/04/2011). Note in the Weather Type column that HZ (haze) was reported for several hours. Dynamically generated viahttp://cdo.ncdc.noaa.gov/qclcd/QCLCD.

# 11U.S. Department of CommerceNational Oceanic & Atmospheric AdministrationQUALITY CONTROLLED LOCALCLIMATOLOGICAL DATA (final)HOURLY OBSERVATIONS TABLEWILLIAMS GATEWAY AIRPORT (23104)PHOENIX, AZ (11/2011)National Climatic Data CenterFederal Building151 Patton AvenueAsheville, North Carolina 28801Elevation: 1382 ft. above sea levelLatitude: 33.3Longitude: -111.666Data Version: VER2DryBulbTempWetBulbTempDewPointTempDateTime(LST)StationTypeSkyConditionsVisibility(SM)WeatherType(F)(C)(F)(C)(F)(C)RelHumd%WindSpeed(MPH)WindDirWindGusts(MPH)StationPressure(in. hg)PressTendNet3-hrChg(mb)SeaLevelPressure(in. hg)ReportTypePrecip.Total(in)Altimeter(in. hg)12345678910111213141516171819202122230404040404040404040404040404040404040404040404040404040404040404040404040400150035005501150135015502150235025503150335035504150435045505150547065007470847094910471147124713471402145615471647175518501947195520152035204720550000000000000000000000000000000000000CLRCLRCLRCLRCLRCLRCLRCLRCLRCLRCLRSCT100CLRCLRCLRCLRFEW150 BKN250SCT150 BKN250SCT150 BKN250SCT150 BKN250SCT150 BKN250SCT150 BKN250FEW150 BKN200FEW150 BKN200FEW150 BKN200FEW150 BKN200FEW150 BKN200BKN075 BKN200FEW150 BKN200FEW150 BKN200FEW150 BKN200OVCCLRVV007CLROVCCLR10.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0020.0035.0035.0035.0035.0035.0035.0035.004.002.502.002.003.002.002.004.005.001.507.004.003.00BLDUBLDUBLDUBLDUBLDUBLDUBLDUHZ-RAHZ6363636161616161616363616463636363616172777781828484868482777372727070707017.017.017.016.016.016.016.016.016.017.017.016.018.017.017.017.017.016.016.022.025.025.027.028.029.029.030.029.028.025.023.022.022.021.021.021.021.047474846474646474748484647474848474647525353555557575858576162M606060M608.18.38.67.78.17.77.78.18.18.68.67.78.58.38.68.68.37.78.111.211.511.512.612.813.813.814.614.214.116.216.4M15.715.315.3M15.327283028302828303030302828283030282830322727282832323434365054545252525452-3.0-2.0-1.0-2.0-1.0-2.0-2.0-1.0-1.0-1.0-1.0-2.0-2.0-2.0-1.0-1.0-2.0-2.0-1.00.0-3.0-3.0-2.0-2.00.00.01.01.02.010.012.012.011.011.011.012.011.026272929312929313129292926272929272931231616141415151617193952M505353M537867710977981076056308141366141114171717172328302523291401501401201501401501501301401401601801600001201101200001401401301401801801802202202102202302202402402302202302426293429293731343930393928.4128.4128.4128.4028.4028.3928.3928.3928.3928.3828.3728.3728.3828.3828.3828.3728.3728.3728.3828.3828.3728.3628.3228.2728.2228.2228.1928.1928.1828.1828.20M28.2028.2028.20M28.21MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA29.8729.8729.8729.8629.8629.8529.8529.8529.8529.8429.8329.8329.8429.8429.8429.8329.8329.8329.8429.8429.8329.8229.7829.7329.6729.6729.6429.6429.6329.6329.6529.6629.6529.6529.6529.6629.66

# 12DryBulbTempWetBulbTempDewPointTempDateTime(LST)StationTypeSkyConditionsVisibility(SM)WeatherType(F) (C)(F)(C) (F) (C)RelHumd%WindSpeed(MPH)WindDirWindGusts(MPH)StationPressure(in. hg)PressTendNet3-hrChg(mb)SeaLevelPressure(in. hg)ReportTypePrecip.Total(in)Altimeter(in. hg)040404040404040404211521352155221522352255231523352355000000000CLRCLRCLRSCT001SCT001SCT001SCT001SCT001SCT001 SCT0854.007.0010.003.005.002.501.752.507.00HZTS-RAHZTSHZHZHZTS68686866666864666320.020.020.019.019.020.018.019.017.060595959585856575815.414.814.815.014.414.313.413.814.654525254525050505512.011.011.012.011.010.010.010.013.0615757656153615775262122221826262820230230230220210220220210230382836253133333128.2128.2128.2128.2128.2028.1928.1828.1828.19MMMMMMMMMAAAAAAAAAAAAAAAAAA29.6629.6629.6629.6629.6529.6429.6329.6329.64Figure A-16.Quality controlled local climatological data hourly observations table for Williams Gateway Airport, Phoenix, Arizona (11/04/2011).Note in the Weather Type column that BLDU (blowing dust) and HZ (haze) was reported for several hours. Dynamically generated viahttp://cdo.ncdc.noaa.gov/qclcd/QCLCD.

# 13U.S. Department of CommerceNational Oceanic & Atmospheric AdministrationQUALITY CONTROLLED LOCALCLIMATOLOGICAL DATA(final)HOURLY OBSERVATIONS TABLEGLENDALE MUNICIPAL AIRPORT (53126)GLENDALE, AZ(11/2011)National Climatic Data CenterFederal Building151 Patton AvenueAsheville, North Carolina 28801Elevation: 1066 ft. above sea levelLatitude: 33.527Longitude: -112.295Data Version: VER2DryBulbTempWetBulbTempDewPointTempDateTime(LST)StationTypeSkyConditionsVisibility(SM)WeatherType(F)(C)(F)(C)(F)(C)RelHumd%WindSpeed(MPH)WindDirWindGusts(MPH)StationPressure(in. hg)PressTendNet3-hrChg(mb)SeaLevelPressure(in. hg)ReportTypePrecip.Total(in)Altimeter(in. hg)12345678910111213141516171819202122230404040404040404040404040404040405470647074808480950104711471247134714521513154716501753185019500000000000000000SCT150 SCT250SCT150 BKN200SCT150 BKN200SCT150 BKN200SCT150 BKN200SCT150 BKN200SCT150 BKN200FEW150 SCT200FEW150 SCT200SCT150 BKN200BKN150BKN150BKN150SCT027 BKN110OVC060BKN09520.0020.0020.0020.0020.0020.0020.0020.0020.0020.004.003.001.001.003.005.00BLDUBLDUBLDUBLDUBLDUBLDU5454576164667277797979797370706612.012.014.016.018.019.022.025.026.026.026.026.023.021.021.019.0434344464848515455556363615958576.26.26.77.88.99.110.512.412.812.817.117.115.914.714.213.930302828302828323232525252504850-1.0-1.0-2.0-2.0-1.0-2.0-2.00.00.00.011.0s11.011.010.09.010.0404033292824191918183939484946570000300035172120171816000000000000VR000000000VR17022022021021019019023292925302628.6728.6728.6828.6928.6928.6728.6328.5828.5428.5028.5028.4928.4828.5028.5228.52MMMMMMMMMMMMMMMMAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA29.8029.8029.8129.8229.8229.8029.7629.7129.6729.6329.6329.6229.6129.6329.6529.65Figure A-17.Quality controlled local climatological data hourly observations table for Glendale Municipal Airport, Glendale, Arizona(11/04/2011). Note in the Weather Type column that BLDU (blowing dust) was reported for several hours. Dynamically generatedviahttp://cdo.ncdc.noaa.gov/qclcd/QCLCD.

# 14U.S. Department of CommerceNational Oceanic & Atmospheric AdministrationQUALITY CONTROLLED LOCAL CLIMATOLOGICAL DATA (final)HOURLY OBSERVATIONS TABLELUKE AFB AIRPORT (23111), GLENDALE, AZ (11/2011)National Climatic Data CenterFederal Building151 Patton AvenueAsheville, North Carolina 28801Elevation: 1085 ft. above sea levelLatitude: 33.55, Longitude: -112.366DryBulbTempWetBulbTempDewPointTempDateTime(LST)StationTypeSkyConditionsVisibility(SM)WeatherType(F)(C)(F)(C)(F)(C)RelHumd%WindSpeed(MPH)WindDirWindGusts(MPH)StationPressure(in. hg)PressTendNet3-hrChg(mb)SeaLevelPressure(in. hg)ReportTypePrecip.Total(in)Altimeter(in. hg)1234567891011121314151617181920212223040404040404040404040404040404040404040404040404040404040404040404040404040404040404040404005501550255035504550555065507550855095510551155125513551455155515581602161516221636164216471655165716581659171217281732173517371738174217481752175317551757175818001800180118061807000000000000000000000000000000000000000000000CLRCLRCLRCLRCLRCLRFEW220CLRCLRCLRCLRCLRCLRFEW140CLRCLRCLRFEW003BKN004BKN004OVC005OVC005OVC005OVC005OVC005OVC006OVC005OVC006OVC006OVC006OVC006OVC005VV005VV005VV005OVC005OVC005OVC005OVC005OVC004OVC004OVCVV004VV003VV00310.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.005.004.004.002.503.003.002.503.003.002.502.502.502.503.002.501.751.251.000.751.001.251.752.001.751.751.251.251.001.000.75HZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZHZ55545353525352546064677376787876757573737373737372727272727070707070707070707070707070707012.512.011.811.811.311.511.212.215.317.719.722.724.325.325.824.224.024.023.023.023.023.023.022.522.022.022.022.022.021.021.021.021.021.021.021.021.021.021.021.021.021.021.021.021.04243434242424244474949525355566262626262626261616060606060605959595959595959595959M5959595.36.16.05.65.75.45.56.48.49.39.310.911.812.813.516.816.916.916.516.516.516.515.916.215.715.715.715.715.715.314.714.714.714.714.714.714.714.714.714.714.7M14.714.714.7232930283027293133322829303337535454545454545253525252525252505050505050505050505050505050-4.9-1.6-1.3-2.5-1.3-2.6-1.9-0.40.40.0-2.1-1.8-1.20.63.011.712.012.012.012.012.012.011.011.411.011.011.011.011.011.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.02938413843374142363023201819234548485252525248505050505050534949494949494949494949M49494968603005003500823242528222525252423242426242829312929292525313231303029332933033036000034000000031000000005002000000020023022022023023022022023022022022023023021021022022022022022022022022022022022022022022022029303232313132373737373434383838383838383828.6928.6828.6628.6528.6528.6428.6428.6528.6628.6528.6328.5928.5528.5028.4728.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.4628.46M28.4628.4628.4686388601001000200604401529.8029.7929.7829.7629.7629.7629.7729.7829.7829.7729.7529.7129.6629.6129.5829.5729.5729.5729.5729.5729.5729.5729.5729.5729.5729.5729.5729.5729.5729.5729.5729.5829.5729.5729.5829.5829.5829.5729.5829.5829.5829.5829.5829.5729.58AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAASPAAAAAA29.8429.8329.8129.8029.8029.7929.7929.8029.8129.8029.7829.7429.7029.6529.6229.6129.6129.6029.6029.6029.6029.6029.6029.6029.6029.6029.6029.6029.6029.6029.6029.6029.6029.6029.6029.6129.6029.6029.6029.6129.6029.6029.6129.6029.61

# 15DryBulbTempWetBulbTempDewPointTempDateTime(LST)StationTypeSkyConditionsVisibility(SM)WeatherType(F) (C) (F)(C) (F)(C)RelHumd%WindSpeed(MPH)WindDirWindGusts(MPH)StationPressure(in. hg)PressTendNet3-hrChg(mb)SeaLevelPressure(in. hg)ReportTypePrecip.Total(in)Altimeter(in. hg)0404040404040404040404040404040404040404040404040404040404040404040404040404040404040404040404040418091812181518241826182918321835184218471854185519011907191719261928195219541955200120052009201320162018202220302031204020522055210221072119214021552159221322342245225322552302230623122317232023550000000000000000000000000000000000000000000000000VV003OVC003VV003OVC003OVC003OVC003OVC003OVC004OVC004OVC004BKN004BKN004SCT004SCT004FEW015SCT027 BKN080SCT027 BKN080BKN036 BKN055 BKN080FEW034 BKN042 BKN055FEW034 BKN046 BKN055FEW033 BKN045 BKN055BKN038 BKN048 BKN090BKN029 BKN037 BKN090BKN030 BKN037BKN038FEW034 OVC042BKN045BKN039 OVC049BKN041 OVC049BKN050 OVC060BKN045 OVC055BKN045 OVC060FEW042 BKN050 BKN065FEW042 SCT055FEW041 SCT060FEW065FEW032 SCT075 SCT095FEW032 SCT070 BKN090SCT060 BKN080FEW065 SCT080BKN070SCT065 SCT080SCT065FEW039 BKN065FEW035 SCT042 BKN065FEW034 SCT045 BKN070FEW034 SCT048 SCT065FEW026 SCT045 BKN055FEW032 BKN049 OVC0601.001.251.001.251.502.001.751.752.003.005.005.005.005.006.007.007.0010.0010.0010.0010.009.008.008.008.009.009.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.007.007.0010.0010.0010.00HZHZHZHZHZHZHZHZHZHZHZHZHZ-RAHZ-RA-RA-RA-RA-RA-RA-RA-RA-RA-RA-RA-RA-RARA-RA-RA-DZ-RA7070706868686868686868686868666464646465646363636161616363636362616161596061616161616161615957575521.021.021.020.020.020.020.020.020.020.020.020.120.020.019.018.018.018.018.018.218.017.017.017.016.016.016.017.017.017.017.016.916.016.016.015.015.716.016.016.016.016.016.216.016.015.014.014.012.85959595858585858585857575858595858575758575857585757575858585856565656565757565655555555565453535214.714.714.714.314.314.314.314.314.314.313.814.014.314.315.014.514.514.014.014.214.014.313.714.313.913.913.914.314.614.614.313.513.313.313.313.413.613.913.313.312.712.712.712.713.312.211.711.711.25050505050505050505048495050545454525252525452545454545455555452525252545454525250505050525050505010.010.010.010.010.010.010.010.010.010.09.09.510.010.012.012.012.011.011.011.111.012.011.012.012.012.012.012.013.013.012.011.211.011.011.012.012.012.011.011.010.010.09.910.011.010.010.010.010.249494953535353535353495153536570706565636573687378787873757573707272728481787272676767677272787883292934302929293028303232313226232528293121262925232015131192424222217141414172021202020252418211321022022021022022022022022021021021021021020020020021021021021022022022021020020020019019023023023022022020020020019019020019019020023027025024023036364138383334343436373737384433343436363939393628283636292928.4628.4628.4628.4628.4628.4728.4728.4728.4728.4728.4728.4728.4728.4728.4728.4728.4728.4728.4728.4728.4828.4728.4828.4828.4928.4928.4928.4928.4928.4928.4928.4928.4928.4928.4828.4728.4728.4728.4728.4628.4628.4428.4428.4628.4628.4628.4628.4728.483800601129.5829.5829.5829.5829.5929.5929.5929.5929.5929.5929.5929.5929.6029.5929.6029.6029.5929.6029.6029.6029.6029.6029.6029.6129.6229.6229.6229.6229.6229.6229.6229.6229.6229.6129.6029.5929.5929.5929.5829.5729.5629.5529.5529.5629.5729.5629.5829.5929.59AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA0.010.010.010.010.010.010.010.010.030.030.030.030.030.030.030.030.030.030.030.03TTTTTTTTTTT0.030.030.030.030.030.0329.6129.6129.6029.6129.6129.6229.6229.6229.6229.6229.6229.6229.6229.6229.6229.6229.6229.6229.6229.6229.6329.6229.6329.6329.6429.6429.6429.6429.6429.6429.6429.6429.6429.6429.6329.6229.6229.6229.6229.6129.6029.5929.5929.6029.6029.6029.6129.6229.63Figure A-18.Quality controlled local climatological data hourly observations table for Luke Air Force Base, Glendale, Arizona (11/04/2011).Note in the Weather Type column that HZ (haze) was reported for several hours. Dynamically generated viahttp://cdo.ncdc.noaa.gov/qclcd/QCLCD.U.S. Department of CommerceNational Oceanic & Atmospheric AdministrationQUALITY CONTROLLED LOCALCLIMATOLOGICAL DATA (final)HOURLY OBSERVATIONS TABLECHANDLER MUNICIPAL AIRPORT (53128)CHANDLER, AZ (11/2011)National Climatic Data CenterFederal Building151 Patton AvenueAsheville, North Carolina 28801Elevation: 1243 ft. above sea levelLatitude: 33.268Longitude: -111.812Data Version: VER2DryBulbTempWetBulbTempDewPointTempDateTime(LST)StationTypeSkyConditionsVisibility(SM)WeatherType(F)(C)(F)(C)(F)(C)RelHumd%WindSpeed(MPH)WindDirWindGusts(MPH)StationPressure(in. hg)PressTendNet3-hrChg(mb)SeaLevelPressure(in. hg)ReportTypePrecip.Total(in)Altimeter(in. hg)123456789101112131415161718192021222304040404040404040404040404040404040550064707470847104711471247133513521450154716541750185219251950204800000000000000000SCT180SCT150 BKN210SCT120 BKN200SCT120 BKN200SCT150 BKN200SCT120 BKN200BKN200 BKN250SCT110SCT110SCT100SCT100SCT100 BKN250SCT100 BKN200SCT100 BKN150SCT050SCT150BKN10015.0040.0040.0040.0040.0040.0025.002.002.001.001.001.002.002.005.005.00MBLDUBLDUBLDUBLDUBLDUBLDUBLDUBLDUBLDU5755616675M818282828177737070706814.013.016.019.024.0M27.028.028.028.027.025.023.021.021.021.020.04443475052M55565656565959595958576.76.18.510.111.1M12.913.113.113.113.215.014.814.714.714.213.82828323427M3030303032454850504848-2.0-2.00.01.0-3.0M-1.0-1.0-1.0-1.00.07.09.010.010.09.09.03336343117M161515151732414949464913558791529243423281734242431090150VR090VR15015017018018021021021019020020019037384039323241314028.4828.4928.4928.4928.4828.4428.3928.3428.3428.3128.3128.3028.3028.3228.3428.3428.33MMMMMMMMMMMMMMMMMAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA29.8029.8129.8129.8129.8029.7629.7029.6529.6529.6229.6229.6129.6129.6329.6529.6529.64Figure A-19.Quality controlled local climatological data hourly observations table for Chandler Municipal Airport, Chandler, Arizona(11/04/2011). Note in the Weather Type column that BLDU (blowing dust) was reported for several hours. Dynamically generatedviahttp://cdo.ncdc.noaa.gov/qclcd/QCLCD.



# 16

# Exceptional Event, Phoenix, November 4, 2011 Appendix B



# 1 

# Appendix B: Media Coverage, Videos, and Images

Video Links

ADEQ visibility camera s in the Phoenix area:

South Mountain: www.phoenixvis.net/videos/mpeg4/SOMT_11042011.mp4

Estrella Mountains: www.phoenixvis.net/videos/mpeg4/ESMO_11042011.mp4

Camelback Mountains: www.phoenixvis.net/videos/mpeg4/CAME_11042011.mp4

Superstition Mountains: www.phoenixvis.net/videos/mpeg4/SUPM_11042011.mp4

Local citizens often create videos during dust st orms, documenting their observations. Here are

a few links to these videos.

http://www.youtube.com/watch?v=-ixD2Vx7DPQ

http://www.youtube.com/watch?v=D1ZqJcUxzU8

http://www.youtube.com/watch?v=k2Z1l8Wd77o

# Exceptional Event, Phoenix, November 4, 2011 Appendix B



# Articles and Image Links

http://www.azcentral.com/news/articles/2011/11/04/20111104arizona-drivers-warned-blowingdust-abrk04-ON.html?nclick_check=1

2 Comment [MJT1]: Did not verify,



# Drought has caused unusually dusty weather in Valley

by Kelsey Pfeffer and Morgan Sailor - Nov. 4, 2011 09:40 PM

The Arizona Republic-12 News Breaking News Team

A severe, ongoing drought has caused some unusually dusty weather in the Valley for this time

of year.

On Friday strong winds and blowing dust forced the intermittent closure of Interstate 8 west and

Interstate 10. The National Weather Service issued a dust-storm warning until late Friday

spanning the Phoenix, Casa Grande to Gila Bend areas, meteorologist Craig Ellis said.

Typically there are localized areas of blowing dust, but large gusts have produced significant

amounts especially along Interstate 8, meteorologist Mike Bruce said.

Evening showers can tame the blowing dust, but threats of dust storms will continue until

Arizona gets some significant rain, Bruce said.

There was an unusually high chance of rain at 80 percent or more in Phoenix, Friday night. The

National Weather Service predicted rainfall amounts to range from one-tenth inch in the lower

deserts to one-half inch in the mountains and foothills of Maricopa and Gila counties.

On Saturday, there is a slight chance of lingering showers in the morning especially in the east

valley with a forecasted high of 65 degrees, which would tie for the record high hit in both 1895

and 1925. The National Weather Service expects a partly cloudy day with cool temperatures.

The clouds are expect to clear up into the evening.

A strong cold front moved across southwest and south-central Arizona including the greater

Phoenix area Friday evening. The cold front is expected to move East on Saturday, according to

the National Weather Service.

There is a 30 percent chance of showers Sunday night extending through Monday, as another

storm system rolls through the Valley. There is a chance of blowing dust on Sunday but not to

the magnitude of Friday's storms, meteorologist Mike Bruce said.

Temperatures are expected to reach the upper 70s la te next week ,which is the average for this

time of year, Ellis said.

# Exceptional Event, Phoenix, November 4, 2011 Appendix B



# 3 

# Dust covers the Camelback Mountain in Phoenix on Friday afternoon. The chance of strong

winds prompted the National Weather Service to issue a wind advisory until 11 pm Friday.

Credit: Rob Schumacher/The Arizona Republic.

# Exceptional Event, Phoenix, November 4, 2011 Appendix B



# http://www.copanews.com/Article.aspx?ID=3199

Strong winds, blowing dust may aff ect I-10 and I-8 travel on Friday

Received article

Friday, November 4, 2011

Threat of low visibility, dust storms could slow traffic

PHOENIX, AZ — With the National Weather Service (NWS) issuing a wind advisory for Friday

(November 4), motorists in southern Arizona could have their travel affected on two major

interstates.

A cold front with strong sustained southwest winds from 25 to 35 mph, including wind gusts up

to 50 mph, is expected to impact most of the st ate. Widespread blowing dust is expected along

stretches of I-10 between Tucson and Phoenix, and from Phoenix to Quartzsite. In addition,

dust is possible on I-8 between Casa Grande and Yuma.

In northern Arizona, an unseasonably strong low pre ssure system and cold front will bring winter

weather conditions this weekend, and could result in the first significant snowfall of the season,

according to the NWS.

The Arizona Department of Transportation (ADOT) urges drivers to take extra precautions as

strong winds over desert areas can result in sudden periods of limited or zero visibility. Motorists

play an important role in safety when operating their vehicles during a dust storm. ADOT and

the Arizona Department of Public Safety recommend the following driving tips when

encountering a dust storm:

Check traffic immediately around your vehicl e (front, back, and to the side) and begin slowing

down.

Do not stop in the travel lane unless the vehicle traffic in front of you has come to a stop.

Look for a safe place to pull completely off the paved portion of the roadway.

Stop the vehicle in a position ensuring it is a safe distance from the main roadway and not

near where any vehicles may travel.

Turn off all vehicle lights.

Set your emergency brake and take the foot off the brake.

Stay in the vehicle and keep your seat belts on.

Wait for the storm to pass over and away from the area before re-entering the roadway.

ADOT, along with DPS, will continue to work as a public safety team to support Arizona’s

highways and drivers and will closely monitor conditions on the highways while maintaining

driver safety.

Drivers planning trips today morrow are urged to monitor travel conditions by calling 5-1-1 within

Arizona, 1-888-411-ROAD outside the state, or via the website www.az511.gov. Because

weather conditions can quickly evolve, drivers are encouraged to regularly check in with

ADOT’s Traveler Information Service. Motorists s hould delay or detour travel plans if necessary.

4

# Exceptional Event, Phoenix, November 4, 2011 Appendix C



# Appendix C: Historical Fluctuation T ime Series Graphs

Figure C-1. 24-hr average PM 10 

# concentrations at the West Phoenix monitor (2007–

2011). The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

1

# Exceptional Event, Phoenix, November 4, 2011 Appendix C



# Figure C-2. 24-hr average PM 10 

# concentrations at the North Phoenix monitor (2007–

2011). The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

Figure C-3. 24-hr average PM 10 

# concentrations at the Glendale Phoenix monitor (2007–

2011). The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

2

# Exceptional Event, Phoenix, November 4, 2011 Appendix C



# Figure C-4. 24-hr average PM 10 

# concentrations at the Central Phoenix monitor (2007–

2011). The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

Figure C-5. 24-hr average PM 10 

# concentrations at the Greenwood monitor (2007–2011).

The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

3

# Exceptional Event, Phoenix, November 4, 2011 Appendix C



# Figure C-6. 24-hr average PM 10 

# concentrations at the South Phoenix monitor (2007–

2011). The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

Figure C-7. 24-hr average PM 10 

# concentrations at the West Chandler monitor (2007–

2011). The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

4

# Exceptional Event, Phoenix, November 4, 2011 Appendix C



# Figure C-8. 24-hr average PM 10 

# concentrations at the West 43rd monitor (2007–2011).

The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

Figure C-9. 24-hr average PM 10 

# concentrations at the Dysart monitor (2007–2011). The

24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and highlighted

by the arrow.

5

# Exceptional Event, Phoenix, November 4, 2011 Appendix C



# Figure C-10. 24-hr average PM 10 

# concentrations at the Buckeye monitor (2007–2011).

The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

Figure C-11. 24-hr average PM 10 

# concentrations at the Zuni Hills monitor (2007–2011).

The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

6

# Exceptional Event, Phoenix, November 4, 2011 Appendix C



# Figure C-12. 24-hr average PM 10 

# concentrations at the Durango monitor (2007–2011).

The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

Figure C-13. 24-hr average PM 10 

# concentrations at the JLG Supersite monitor (2007–

2011). The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

7

# Exceptional Event, Phoenix, November 4, 2011 Appendix C



# Figure C-14. 24-hr average PM 10 

# concentrations at the Fort McDowell/Yuma Frank

monitor (2007–2011). The 24-hr average PM 10 

# concentration on November 4, 2011, is

shown in red and highlighted by the arrow.

F igure C-15. 24-hr average PM 10 

# concentrations at the Apache Junction monitor (2007–

2011). The 24-hr average PM 10 

# concentration on November 4, 2011, is shown in red and

highlighted by the arrow.

8

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# D-1 RISK LEVEL



# HIGH

+

+ 

# Appendix D:

ADEQ and NWS Fore cast Products

MARICOPA COUNTY DUST CONTROL FORECAST

ISSUED THURSDAY, NOVEMBER 3, 2011

Three-day weather outlook:

A very strong trough of low pressure will bring unseasonably cool air and significant winds. Blowing dust is expected across a much

of the desert southwest as gust will likely top 50 mph. There’s a 70% chance of evening showers in Phoenix continuing into earl y

Saturday. Winds drop of considerably Saturday afternoon. Daytime temperatures will be in the upper 60s through the weekend with

lows in the 40s. The risk of exceeding the 24-hr PM10 health standard in Phoenix will be HIGH on Friday, dropping to Low by

Saturday.



# R I S K F A C T O R S

WINDS STAGNATION UNHEALTHY PM-10

Day 1: Fri 11/04/2011 Northwest winds around

25 to 35 mph are

expected with gusts near +

50 mph at times (70%

chance of showers late). Little to not stagnation

is expected. =

Day 2: Sat 11/05/2011 Southwest winds around

5 to 10 mph are

expected (10% chance

for morning showers). Increasingly stagnant

+ conditions will develop

during the afternoon. = 

# LOW

Day 3: Sun 11/06/2011 South-southwest winds

around 5 to 10 mph are

expected. Rather stagnant

+ conditions are likely

much of the day. = 

# LOW

EXTENDED OUTLOOK

Day 4: Mon 11/07/2011 West winds around 5 to

10 mph are expected. Rather stagnant

conditions are likely

much of the day. = 

# LOW

Day 5: Tue 11/08/2011 Mostly light winds are

expected. Rather stagnant

conditions are likely

much of the day. = 

# LOW

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# The Maricopa County Dust Control Action Forecast is issued to assist in the planning of work activities to

help reduce dust pollution. A recorded message of this forecast can be accessed at 602-771-2368 . To

review the complete air quality fore cast for the Phoenix metropolitan ar ea, as well as the health impacts

and reduction methods for di fferent air pollutants, call 602-771-2367 for recorded forecast information or

click on ADEQ's Air Quality Forecast at http://www.azdeq.gov/environ/air/ozone/ensemble.pdf

.

JRP 04/28/2011



# D-2

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# D-3 FORECAST

DATE

NOTICES

(*SEE BELOW

FOR DETAILS)

AIR POLLUTANT 

# YESTERDAY

WED 11/02/2011

DUST

Highest AQI Reading/Site

(Preliminary data only) 

# TODAY

THU 11/03/2011 

# TOMORROW

FRI 11/04/2011

(PM10)

DUST

COUNTY-ISSUED

NO BURN DAY 

# EXTENDED

SAT 11/05/2011



# O3* 42

MULTIPLE

LOCATIONS 

# 38

GOOD 

# 35

GOOD 

# 38

GOOD



# CO* 8

TEMPE 

# 23

GOOD 

# 9

GOOD 

# 17

GOOD



# PM-10* 282

ZUNI HILLS 

# 40

GOOD 

# 195

UNHEALTHY 

# 35

GOOD



# PM-2.5* 36

DURANGO &

DYSART 

# 60

MODERATE 

# 45

GOOD 

# 53

MODERATE 

# VERY UNHEALTHY (201-300)

UNHEALTHY (151-200)

UNHEALTHY FOR SENSITIVE GROUPS (101-150)

MODERATE (51-100)

GOOD (0-50)

For more information visit:

http://www.airnow.gov/index.cfm?action=aqibasics.aqi

*LINK TO 2011 AIR POLLUTION EXCEEDANCE GRAPH* 

# AIR QUALITY FO RECAST FOR FRIDAY, NOVEMBER 4, 2011

This report is updated by 1:00 p.m. Sunday thru Friday and is valid

for areas within and bordering Maricopa County in Arizona

* O3 = Ozone CO = Carbon Monoxide PM-10 = Particles 10 micr ons & smaller PM-2.5 = Particles smaller than 2.5 microns



# *“ Ozone Health Watch ” means that the highest concentration of OZONE may approach the federal health standard.

# Exceptional Event, Phoenix, November 4, 2011 Appendix D

“ PM-10 or PM-2.5 Health Watch ” means that the highest concentration of PM-10 or PM-2.5 may approach the federal health standard.

“ High Pollution Advisory ” means that the highest concentration of OZONE, PM-10, or PM-2.5 may exceed the federal health standard.

“ DUST ” means that short periods of high PM-10 concentrations caused by outflow from thunderstorms are possible.



# D-4

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# D-5 Health message for Thursday, November 3: Unusually sensitive people should

consider limiting prolonged exertion outdoors.

Health message for Friday, November 4: People with heart or lung disease, older

adults, and children should avoid all physical activity outdoors. Everyone else

should avoid prolonged or heavy exertion.

...A PM10 HIGH POLLUTION ADVISORY HAS BEEN ISSUED FOR FRIDAY, NOV. 4, 2011...

Wednesday’s cold front brought strong winds to the region with gusts reaching 50 mph at times in the

northwest part of the Valley. It was there that the hi ghest levels of PM10 were recorded (282 AQI at Zuni

Hills, 76 AQI at Dysart). As winds decreased to a steady 10-20 mph, the air cleared out well across the

forecast area. Thursday’s winds are considerably lo wer and will remain that way through early Friday.

With Wednesday’s event in the books, we’re looking ahead at Friday’s system. This trough of low

pressure will drop a bit further south, generating much stronger winds across the southwest. Widespread

dust is likely from southern Calif ornia east across Arizona deserts in cluding the cities of Yuma, Phoenix,

Casa Grande and Tucson. The timing of the stronges t winds in Phoenix will be between 11am and 11pm.

Fortunately because the system is dropping further sout h, it will tap into a good fetch of moisture. We will

see showers develop across the region around 3-5pm with the heaviest expected around 11pm. Totals will

generally be around a tenth to a half an inch with more near thunderstorms and in the upslope areas. The

rain should help wash out any lingering/suspended dust.

Colder air will fill in behind the system, dropping daytime temperatures into upper 60s Saturday and

Sunday with lows in the 40s.

NOTE: Multiple-vehicle accidents are not uncommon along Arizona freeways when similar wind/dust

events occur. This is especially a concern for drivers along I-10 between California and Phoenix and

between Phoenix and Tucson, as well as I-8 between Casa Grande and Yuma. Those expecting to travel

along these routes may want to pay close attention to the Nation Weather Service and Arizona Department

of Transportation for the latest weather information and road conditions.

C heck back tomorrow for the more. Un til then, have a good day! -J.Paul

MONITORING SITE MAPS

STATIC M A P htt p ://www.azde q

. g ov/environ/air/monitorin g /ima g es/ma p

. jp g

http://aqwww.maricopa.gov/AirMonitoring/SitePollutionMap.aspx

http://156.42.96.39/alert/Google/air.html INTERACTIVE MAPS

http://www.airnow.gov/



# POLLUTION MONITOR READINGS FOR WEDNESDAY, NOVEMBER 2, 2011



# O3 (OZONE)

Info on current 8-hour ozone standard: http://www.epa.gov/air/ozonepollution/pdfs/2008_03_aqi_changes.pdf

For archived AQI maps go to: http://www.airnow.gov/index.cfm?action=airnow.maps

SITE NAME MAX 8-HR VALUE (PPB) MAX AQI AQI COLOR CODE

Apache Junction (Pinal County) 

# 43 36

Blue Point 46 39

Central Phoenix 44 37

Fountain Hills 47 40

North Phoenix 48 41

Phoenix Supersite 50 42

Pinnacle Peak 49 42

South Phoenix 45 38

South Scottsdale 44 37

West Phoenix 49 42

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# 6 

# CO (CARBON MONOXIDE)

SITE NAME MAX 8-HR VALUE (PPM) MAX AQI AQI COLOR CODE

Buckeye 0.2 2

Central Phoenix 0.5 6

Dysart 0.2 2

Glendale 0.2 2

Greenwood 0.6 7

Mesa 0.6 7

North Phoenix 0.5 6

South Phoenix 0.5 6

South Scottsdale 0.6 7

Tempe 0.7 8

West Chandler 0.5 6

West Phoenix 0.5 6



# PM-10 (PARTICLES)

SITE NAME MAX 24-HR VALUE (μg/m3) 

# MAX AQI AQI COLOR CODE

Buckeye 51.0 46

Central Phoenix 25.7 23

Combs School (Pinal County) 

# 141.3 93

Durango 39.5 26

Dysart 105.0 76

Glendale 35.5 32

Greenwood 37.8 34

Higley 29.6 27

Maricopa (Pinal County) 40.0 37

North Phoenix 22.1 20

Phoenix Supersite 30.0 27

South Phoenix 54.0 49

West Chandler 25.2 23

West Forty Third 37.0 34

West Phoenix 48.4 44

Zuni Hills 441.9 282



# PM-2.5 (PARTICLES)

(Some data derived from light-scattering equipment)



# For maps go to: http://www.airnow.gov /

SITE NAME MAX 24-HR VALUE (μg/m3) 

# MAX AQI AQI COLOR CODE

Durango 11.0 36

Dysart 11.2 36

Estrella Mountain Park 7.3 24

Glendale 3.7 12

Phoenix Supersite 5.4 18

North Phoenix 3.8 12

South Phoenix 6.7 22

Vehicle Emissions Lab 3.1 10

West Phoenix 1.6 5

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# 7 

# Statements, Advisories, and Warnings issued by the National Weather Service office in

Phoenix, AZ pertaining to this dust storm event:

WWUS85 KPSR 030213

SPSPSR

SPECIAL WEATHER STATEMENT

NATIONAL WEATHER SERVICE PHOENIX AZ

713 PM MST WED NOV 2 2011

AZZ020>028-CAZ030>033-031300-

LOWER COLORADO RIVER VALLEY AZ-WEST CENTRAL DESERTSNORTHWEST MARICOPA COUNTY-GREATER PHOENIX AREASOUTHERN GILA COUNTY/TONTO NATIONAL FOREST FOOTHILLSYUMA/MARTINEZ LAKE AND VICINITY-SOUTHWEST DESERTSSOUTHWEST MARICOPA COUNTY-NORTHWEST AND NORTH CENTRAL PINAL COUNTYJOSHUA TREE NATIONAL PARK-LOWER COLORADO RIVER VALLEY CARIVERSIDE COUNTY/EASTERN DESERTS-IMPERIAL COUNTYINCLUDING THE CITIES OF...EHRENBERG...PARKER...BOUSE...QUARTZSITE...

SALOME...BUCKEYE...LAKE PLEASANT...MORRISTOWN...NEW RIVER...

TONOPAH...WICKENBURG...CAREFREE...CAVE CREEK...CHANDLER...

FOUNTAIN HILLS...GILBERT...GLENDALE...MESA...PEORIA...PHOENIX...

SCOTTSDALE...SUN CITY...TEMPE...GLOBE...MIAMI...SAN CARLOS...

SUPERIOR...TOP-OF-THE-WORLD...ALSO INCLUDING APACHE...BARTLETT...

CANYON...HORSESHOE...ROOSEVELT...AND SAGUARO LAKES...

FORTUNA FOOTHILLS...SAN LUIS...SOMERTON...YUMA...DATELAND...TACNA...

WELLTON...GILA BEND...APACHE JUNCTION...CASA GRANDE...COOLIDGE...

FLORENCE...COTTONWOOD VISITOR CENTER...KEYS VIEW...LOST HORSE...

BLYTHE...CHIRIACO SUMMIT...DESERT CENTER...EAGLE MOUNTAIN...

BRAWLEY...CALEXICO...EL CENTRO...GLAMIS...IMPERIAL...

AND THE SALTON SEA

713 PM MST WED NOV 2 2011 /713 PM PDT WED NOV 2 2011/

...PACIFIC LOW TO BRING UNSETTLED...WINDY AND MUCH COOLER WEATHER TO

THE AREA FRIDAY INTO SATURDAY...

THE SECOND IN A SERIES OF COLD PACIFIC LOW PRESSURE SYSTEMS IS SLATED

TO MOVE PROGRESSIVELY EAST ACROSS SO UTHEAST CALIFORNIA AND ARIZONA

FRIDAY INTO SATURDAY...BRINGING WITH IT STRONG GUSTY WINDS...MUCH

COOLER TEMPERATURES AND SHOWERY CONDITIONS. THE STRONG COLD FRONT

WILL LOWER TEMPERATURES ACROSS SO UTHEAST CALIFORNIA AND SOUTHWEST

ARIZONA INTO THE UPPER 60S AND LOW 70S ON FRIDAY. THE FRONT WILL EXIT

TO THE EAST ON FRIDAY NIGHT AND BY SATURDAY MOST OF THE LOWER

CALIFORNIA AND ARIZONA DESERTS WILL SEE HIGH TEMPERATURES IN THE 60S.

STRONG GUSTY SOUTH TO SOUTHWEST WINDS WILL DEVELOP DURING THE LATE

MORNING AND AFTERNOON HOURS FRIDAY AHEAD OF THE COLD FRONT. SUSTAINED

SPEEDS BETWEEN 20 AND 30 MPH ARE LIKELY AND PEAK GUSTS COULD REACH TO

NEAR 50 MPH. WINDS WILL CONTINUE TO BE STRONG AND GUSTY AS THE COLD

FRONT PASSES AND WILL SWING TOWARDS THE WEST OR NORTHWEST. IT IS

LIKELY THAT A WIND ADVISORY WILL BE NEEDED ACROSS MUCH OF THE AREA

DURING THE AFTERNOON AND EVENING HOURS ON FRIDAY.

GIVEN THE CURRENTLY DRY CONDITIONS...THE STRONG WINDS WILL LIKELY

GENERATE AREAS OF BLOWING SAND...DUST AND DIRT WHICH WILL

NECESSITATE THE ISSUANCE OF BOTH DUST STORM ADVISORIES AND DUST STORM

WARNINGS OVER PORTIONS OF THE LO WER CALIFORNIA AND ARIZONA DESERT

FRIDAY AFTERNOON AND EVENING.

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# 8 FINALLY...THERE WILL BE A CHANCE FOR SHOWERS FRIDAY IN SOUTHEAST

CALIFORNIA...AND AS THE FRONT MOVES ACROSS ARIZONA FRIDAY NIGHT THE

CHANCES WILL SHIFT INTO SOUTHERN AND SOUTH CENTRAL ARIZONA. SHOWERS

WILL BE NUMEROUS OVER THE HIGHER TERRAIN OF SOUTHERN GILA COUNTY

FRIDAY NIGHT. RAINFALL TOTALS OF ONE HALF INCH OR MORE ARE POSSIBLE

ACROSS SOUTH CENTRAL ARIZONA FRIDAY NIGHT...ESPECIALLY OVER FAVORED

UPSLOPE AREAS NORTH AND EAST OF PHOENIX. BY SATURDAY MORNING THE COLD

AIR ASSOCIATED WITH THE FRONT WILL LOWER SNOW LEVELS TO NEAR 5000

FEET...HOWEVER NO SIGNIFICANT SNOW FALL ACCUMULATIONS ARE EXPECTED AT

THAT LEVEL.

STAY UP-TO-DATE ON THE LATEST FORECASTS BY LISTENING TO WEATHER RADIO

ON THE PUBLIC SERVICE BAND. MORE DETAILED INFORMATION IS AVAILABLE

FROM THE NATIONAL WEATHER SERVICE IN PHOENIX ON THE INTERNET AT

WEATHER.GOV/PHOENIX

WWUS75 KPSR 030958

NPWPSR

URGENT - WEATHER MESSAGE

NATIONAL WEATHER SERVICE PHOENIX AZ

258 AM MST THU NOV 3 2011

AZZ021>024-026>028-032200-

/O.NEW.KPSR.WI.Y.0033.111104T1800Z-111105T0300Z/

WEST CENTRAL DESERTS-NORTHWEST MARICOPA COUNTYGREATER PHOENIX AREASOUTHERN GILA COUNTY/TONTO NATIONAL FOREST FOOTHILLSSOUTHWEST DESERTS-SOUTHWEST MARICOPA COUNTYNORTHWEST AND NORTH CENTRAL PINAL COUNTYINCLUDING THE CITIES OF...QUARTZSITE...SALOME...BUCKEYE...

NEW RIVER...WICKENBURG...MESA...PHOENIX...GLOBE...MIAMI...

SAN CARLOS...SUPERIOR...TOP-OF-THE-WORLD...TACNA...WELLTON...

GILA BEND...APACHE JUNCTION...CASA GRANDE...FLORENCE

258 AM MST THU NOV 3 2011

...WIND ADVISORY IN EFFECT FROM 11 AM TO 8 PM MST FRIDAY...

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A WIND

ADVISORY...WHICH IS IN EFFECT FROM 11 AM TO 8 PM MST FRIDAY.

* AFFECTED AREA: LA PAZ...YUMA...MARICOPA...NORTHWEST PINAL...AND

SOUTHERN GILA COUNTIES.

* LOCATIONS INCLUDE: THE ENTIRE PHOENIX METROPOLITAN AREA...GILA

BEND...TACNA...WELLTON...GLOBE...MIAMI...SAN CARLOS...WICKENBURG

...QUARTZSITE... SALOME...CASA GRANDE...FLORENCE...INTERSTATE TEN

FROM NEAR CASA GRANDE WEST THROUGH PHOENIX AND TOWARD QUARTZSITE...

AND INTERSTATE EIGHT FROM NEAR CASA GRANDE WEST TOWARD YUMA.

* TIMING: BEGINNING LATE FRIDAY MORNING AND CONTINUING INTO FRIDAY

EVENING.

* WINDS: SUSTAINED SOUTHERLY WINDS 25 TO 35 MPH GUSTING TO 50 MPH.

* IMPACTS: TRAVEL MAY BE DIFFICULT...ESPECIALLY ALONG EAST TO WEST

ORIENTED ROADS WHICH INCLUDES INTERSTATES EIGHT AND TEN. WIDESPREAD

AREAS OF BLOWING DUST ARE LIKELY WITH LOCALIZED AREAS OF VERY DENSE

BLOWING DUST POSSIBLE. MOTORISTS SHOULD BE PREPARED FOR VERY QUICK

AND DRASTIC REDUCTIONS IN VISIBILITY. SMALL UNSECURED OBJECTS MAY

BECOME AIRBORNE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WIND ADVISORY MEANS THAT SUSTAINE D WIND SPEEDS OF BETWEEN 30 AND 40

MPH ARE EXPECTED...OR WIND GUSTS OF BETWEEN 40 AND 58 MPH. WINDS THIS

STRONG CAN MAKE DRIVING DIFFIC ULT...ESPECIALLY FOR HIGH PROFILE

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# 9 VEHICLES. IN ADDITION...STRONG WINDS OVER DESERT AREAS COULD RESULT

IN BRIEFLY LOWERED VISIBILITIES TO WELL UNDER A MILE AT TIMES IN

BLOWING DUST OR BLOWING SAND. USE EXTRA CAUTION.

&&

$$

NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT

WEATHER.GOV/PHOENIX

WWUS85 KPSR 031638

SPSPSR

SPECIAL WEATHER STATEMENT

NATIONAL WEATHER SERVICE PHOENIX AZ

938 AM MST THU NOV 3 2011

AZZ020>028-CAZ030>033-041330-

LOWER COLORADO RIVER VALLEY AZ-WEST CENTRAL DESERTSNORTHWEST MARICOPA COUNTY-GREATER PHOENIX AREASOUTHERN GILA COUNTY/TONTO NATIONAL FOREST FOOTHILLSYUMA/MARTINEZ LAKE AND VICINITY-SOUTHWEST DESERTSSOUTHWEST MARICOPA COUNTY-NORTHWEST AND NORTH CENTRAL PINAL COUNTYJOSHUA TREE NATIONAL PARK-LOWER COLORADO RIVER VALLEY CARIVERSIDE COUNTY/EASTERN DESERTS-IMPERIAL COUNTYINCLUDING THE CITIES OF...EHRENBERG...PARKER...BOUSE...QUARTZSITE...

SALOME...BUCKEYE...LAKE PLEASANT...MORRISTOWN...NEW RIVER...

TONOPAH...WICKENBURG...CAREFREE...CAVE CREEK...CHANDLER...

FOUNTAIN HILLS...GILBERT...GLENDALE...MESA...PEORIA...PHOENIX...

SCOTTSDALE...SUN CITY...TEMPE...GLOBE...MIAMI...SAN CARLOS...

SUPERIOR...TOP-OF-THE-WORLD...ALSO INCLUDING APACHE...BARTLETT...

CANYON...HORSESHOE...ROOSEVELT...AND SAGUARO LAKES...

FORTUNA FOOTHILLS...SAN LUIS...SOMERTON...YUMA...DATELAND...TACNA...

WELLTON...GILA BEND...APACHE JUNCTION...CASA GRANDE...COOLIDGE...

FLORENCE...COTTONWOOD VISITOR CENTER...KEYS VIEW...LOST HORSE...

BLYTHE...CHIRIACO SUMMIT...DESERT CENTER...EAGLE MOUNTAIN...

BRAWLEY...CALEXICO...EL CENTRO...GLAMIS...IMPERIAL...

AND THE SALTON SEA

938 AM MST THU NOV 3 2011 /938 AM PDT THU NOV 3 2011/

...PACIFIC STORM SYSTEM WITH STRONG WINDS...BLOWING DUST...SHOWERS...

POSSIBLE THUNDERSTORMS...AND MUCH COOLER WEATHER ON THE WAY...

WINDS FROM THE SOUTH AND WEST ARE EXPECTED TO INCREASE ACROSS

SOUTHEAST CALIFORNIA...AND SOUTHWEST AND SOUTH-CENTRAL ARIZONA LATE

FRIDAY MORNING THROUGH FRIDAY EVENING AHEAD OF A PACIFIC COLD FRONT.

STRONG CROSS WINDS ARE EXPECTED ACRO SS SOME ROADS AND HIGHWAYS. THE

STRONGEST WINDS ARE EXPECTED IN SOUTHWEST AND SOUTH-CENTRAL ARIZONA

WITH GUSTS TO 50 MPH FRIDAY AFTERNOON AND FRIDAY EVENING.

THE STRONG GUSTY WINDS ARE EXPECTED TO CAUSE AREAS OF DENSE BLOWING

SAND AND DUST THE DESERT AREAS. THIS INCLUDES INTERSTATES 10 AND 8

BETWEEN TUCSON...CASA GRANDE...PHOENIX...GILA BEND...YUMA...AND EL

CENTRO. THE AREA BETWEEN TUCSON...CASA GRANDE...PHOENIX...AND GILA

BEND IS ESPECIALLY PRONE TO VERY DENSE BLOWING DUST WITH NEAR ZERO

VISIBILITY POSSIBLE FRIDAY AFTERNOON AND FRIDAY EVENING.

THE DENSE BLOWING DUST COULD OCCUR IN THE GREATER PHOENIX AREA DURING

THE COMMUTER RUSH HOUR LATE FRIDAY AFTERNOON AND EARLY EVENING.

IF YOU SEE A DUST STORM APPROACHING OR GET CAUGHT IN ONE...PULL OFF

THE ROAD AS FAR AS SAFELY POSSIBLE...PUT YOUR VEHICLE IN PARK...KEEP

YOUR FOOT OFF THE BRAKE PEDAL...AND TURN YOUR LIGHTS ALL THE WAY OFF.

THE PACIFIC COLD FRONT WITH A CHANCE OF SHOWERS AND THUNDERSTORMS WILL

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# 10 MOVE FROM WEST TO EAST ACROSS SOUTHEAST CALIFORNIA AND SOUTHWEST

ARIZONA LATE FRIDAY AFTERNOON AND FRIDAY EVENING WITH SHOWERS LIKELY

IN SOUTH-CENTRAL ARIZONA FRIDAY NIGHT ALONG WITH A CHANCE OF

THUNDERSTORMS.

MOST OF THE RAIN IS EXPECTED TO BE IN SOUTH-CENTRAL ARIZONA INCLUDING

THE GREATER PHOENIX AREA FRIDAY NIGHT. THE SHOWERS AND CHANCE OF

THUNDERSTORMS WILL PROBABLY NOT REACH THE PHOENIX AREA UNTIL LATE

FRIDAY EVENING.

RAINFALL AMOUNTS ARE EXPECTED TO RANGE FROM LESS THAN A TENTH OF AN

INCH IN SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING EL

CENTRO AND YUMA. RAINFALL AMOUNTS ARE EXPECTED TO RANGE FROM 1 TENTH

OF AN INCH TO MORE THAN A QUARTER OF AN INCH IN THE SOUTH-CENTRAL

ARIZONA DESERT INCLUDING THE PHOENIX AREA TO MORE THAN A HALF INCH

IN THE HIGHER TERRAIN NORTH AND EAST OF THE GREATER PHOENIX AREA.

COLDER AIR WILL MOVE IN BEHIND THE FRONT WITH EARLY MORNING

TEMPERATURES DROPPING INTO THE U PPER 30S AND 40S IN MOST DESERT

LOCATIONS SATURDAY MORNING. AND...COMPARED WITH TODAY...HIGH

TEMPERATURES ARE EXPECTED TO BE 10 TO 20 DEGREES COLDER SATURDAY WITH

HIGHS BETWEEN 60 AND 70 IN THE DESERT AREAS INCLUDING PHOENIX...YUMA

AND EL CENTRO.

THE SNOW LEVEL WILL LOWER TO NEAR 5000 FEET BY SATURDAY MORNING.

HOWEVER...MOST OF THE PRECIPITATION WILL HAVE ENDED BY THEN.

THUS...NO SIGNIFICANT SNOWFALL ACCUMULATION IS EXPECTED AT THAT

LEVEL.

STAY UP-TO-DATE ON THE LATEST FORECASTS BY LISTENING TO WEATHER

RADIO ON THE PUBLIC SERVICE BAND. MORE DETAILED INFORMATION IS

AVAILABLE FROM THE NATIONAL WEATHER SERVICE IN PHOENIX ON THE

INTERNET AT

WEATHER.GOV/PHOENIX

WWUS75 KPSR 040347

NPWPSR

URGENT - WEATHER MESSAGE

NATIONAL WEATHER SERVICE PHOENIX AZ

847 PM MST THU NOV 3 2011

AZZ021>023-026>028-041315-

/O.NEW.KPSR.DU.Y.0003.111104T1800Z-111105T0300Z/

/O.CON.KPSR.WI.Y.0033.111104T1800Z-111105T0300Z/

WEST CENTRAL DESERTS-NORTHWEST MARICOPA COUNTYGREATER PHOENIX AREA-SOUTHWEST DESERTS-SOUTHWEST MARICOPA COUNTYNORTHWEST AND NORTH CENTRAL PINAL COUNTYINCLUDING THE CITIES OF...QUARTZSITE...SALOME...BUCKEYE...

NEW RIVER...WICKENBURG...MESA...PHOENIX...TACNA...WELLTON...

GILA BEND...APACHE JUNCTION...CASA GRANDE...FLORENCE

847 PM MST THU NOV 3 2011

...BLOWING DUST ADVISORY IN EFFECT FROM 11 AM TO 8 PM MST

FRIDAY...

...WIND ADVISORY REMAINS IN EFFECT FROM 11 AM TO 8 PM MST

FRIDAY...

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A BLOWING DUST

ADVISORY...WHICH IS IN EFFECT FROM 11 AM TO 8 PM MST FRIDAY. A

WIND ADVISORY REMAINS IN EFFECT FROM 11 AM TO 8 PM MST FRIDAY.

* AFFECTED AREA: LA PAZ...YUMA...MARICOPA...NORTHWEST PINAL...

AND SOUTHERN GILA COUNTIES.

* LOCATIONS INCLUDE: GILA BEND...TACNA...WELLTON...BUCKEYE...

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# 11 MESA...PHOENIX...NEW RIVER...WICKENBURG...QUARTZSITE...

SALOME...APACHE JUNCTION...CASA GRANDE...FLORENCE. AREAS ESPECIALLY

IMPACTED BY THE BLOWING DUST ADVISORY INCLUDE THE GREATER PHOENIX

AREA SOUTHEASTWARD DOWN THE INTERSTATE 10 CORRIDOR TOWARDS CASA

GRANDE AND COOLIDGE.

* TIMING: BEGINNING LATE FRIDAY MORNING AND CONTINUING INTO

FRIDAY EVENING.

* WINDS: SUSTAINED SOUTHERLY WINDS 25 TO 35 MPH GUSTING TO50

MPH.

* VISIBILITIES: AREAS OF LOWERED VISIBILITY BETWEEN 3 AND 5 MILES

LOCALLY BELOW ONE MILE.

* IMPACTS: TRAVEL MAY BE DIFFICULT...ESPECIALLY ALONG EAST TO WEST

ORIENTED ROADS WHICH INCLUDES INTERSTATES EIGHT AND TEN. STRONG

CROSSWINDS WILL PRODUCE DANGEROUS DRIVING CONDITIONS FOR DRIVERS OF

HIGH PROFILE VEHICLES. WIDESPREAD AREAS OF BLOWING DUST ARE LIKELY

WITH LOCALIZED AREAS OF VERY DENS E BLOWING DUST PO SSIBLE. MOTORISTS

SHOULD BE PREPARED FOR VERY QUICK AND DRASTIC REDUCTIONS IN

VISIBILITY. SMALL UNSECURED OBJECTS MAY BECOME AIRBORNE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WIND ADVISORY MEANS THAT SUSTAINED WIND SPEEDS OF BETWEEN

30 AND 40 MPH ARE EXPECTED...OR WIND GUSTS OF BETWEEN 40 AND

58 MPH. WINDS THIS STRONG CAN MAKE DRIVING DIFFICULT...ESPECIALLY

FOR HIGH PROFILE VEHICLES. IN AD DITION...STRONG WINDS OVER DESERT

AREAS COULD RESULT IN BRIEFLY LOWERED VISIBILITIES TO WELL UNDER

A MILE AT TIMES IN BLOWING DUST OR BLOWING SAND. USE EXTRA

CAUTION.

A BLOWING DUST ADVISORY MEANS THAT BLOWING DUST WILL RESTRICT

VISIBILITIES. SOME LOCATIONS WILL SEE VISIBILITIES FALL BELOW ONE

MILE. TRAVELERS ARE URGED TO USE EXTRA CAUTION.

WWUS75 KPSR 041117

NPWPSR

URGENT - WEATHER MESSAGE

NATIONAL WEATHER SERVICE PHOENIX AZ

417 AM MST FRI NOV 4 2011

AZZ022-023-027-028-042330-

/O.EXT.KPSR.WI.Y.0033.111104T1800Z-111105T0600Z/

/O.CON.KPSR.DU.Y.0003.111104T1800Z-111105T0300Z/

NORTHWEST MARICOPA COUNTY-GREATER PHOENIX AREASOUTHWEST MARICOPA COUNTYNORTHWEST AND NORTH CENTRAL PINAL COUNTYINCLUDING THE CITIES OF...BUCKEYE...NEW RIVER...WICKENBURG...

MESA...PHOENIX...GILA BEND...APACHE JUNCTION...CASA GRANDE...

FLORENCE

417 AM MST FRI NOV 4 2011

...WIND ADVISORY NOW IN EFFECT FROM 11 AM THIS MORNING TO 11 PM

MST THIS EVENING...

...BLOWING DUST ADVISORY REMAINS IN EFFECT FROM 11 AM THIS

MORNING TO 8 PM MST THIS EVENING...

THE WIND ADVISORY IS NOW IN EFFECT FROM 11 AM THIS MORNING TO

11 PM MST THIS EVENING. A BLOWING DUST ADVISORY REMAINS IN EFFECT

FROM 11 AM THIS MORNING TO 8 PM MST THIS EVENING.

* AFFECTED AREA: MARICOPA...AND NORTHWEST PINAL COUNTIES FOR BOTH

DUST AND WINDS.

* LOCATIONS INCLUDE: DUST PRONE AREAS NEAR FARM FIELDS AND

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# 12 CONSTRUCTION SITES WILL BE MOST SUSCEPTIBLE...ESPECIALLY THE

INTERSTATE 10 CORRIDOR THROUGH PINAL COUNTY. OTHERWISE...STRONG

WINDS WILL AFFECT LOCATIONS INCLUDING...BUT NOT LIMITED TO...GILA

BEND...TACNA...WELLTON...BUCKEYE... MESA...PHOENIX...NEW

RIVER...WICKENBURG...QUARTZSITE ... SALOME...APACHE JUNCTION...CASA

GRANDE...FLORENCE.

* TIMING: BEGINNING LATE THIS MORNING AND CONTINUING THROUGH THIS

EVENING.

* WINDS: SUSTAINED SOUTH AND SOUTHWESTERLY WINDS 25 TO 35 MPH GUSTING

40 TO 50 MPH.

* VISIBILITIES: BROAD AREAS REDUCED TO 3 TO 5 MILES...LOCALLY BELOW ONE

MILE.

* IMPACTS: BLOWING DUST WILL CREATE HAZARDOUS DRIVING CONDITIONS DUE

TO REDUCED VISIBILITIES. STRONG WINDS WILL MAKE VEHICLE HANDLING

MORE DIFFICULT DUE TO CROSS-WINDS...ESPECIALLY FOR HIGH PROFILE

VEHICLES. IN ADDITION...SMALL UNSECURED OBJECTS AROUND HOMES AND

BUSINESSES MAY BECOME AIRBORNE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOTORISTS SHOULD USE EXTRA CAUTION AND BE PREPARED FOR VERY QUICK AND

DRASTIC REDUCTIONS IN VISIBILITY...ESPECIALLY ALONG INTERSTATES 10

AND 8. IF YOU ENCOUNTER VERY LOW VISIBILITY ON THE ROADWAY...PULL

OFF THE ROAD AS FAR AS POSSIBLE AND PARK...TURN OFF THE LIGHTS AND

KEEP YOUR FOOT OFF THE BRAKE.

WWUS75 KPSR 042107

NPWPSR

URGENT - WEATHER MESSAGE

NATIONAL WEATHER SERVICE PHOENIX AZ

207 PM MST FRI NOV 4 2011

AZZ023-027-028-050600-

/O.UPG.KPSR.DU.Y.0003.000000T0000Z-111105T0300Z/

/O.NEW.KPSR.DS.W.0024.111104T2107Z-111105T0300Z/

/O.CON.KPSR.WI.Y.0033.000000T0000Z-111105T0600Z/

GREATER PHOENIX AREA-SOUTHWEST MARICOPA COUNTYNORTHWEST AND NORTH CENTRAL PINAL COUNTYINCLUDING THE CITIES OF...BUCKEYE...MESA...PHOENIX...GILA BEND...

APACHE JUNCTION...CASA GRANDE...FLORENCE

207 PM MST FRI NOV 4 2011

...DUST STORM WARNING IN EFFECT UNTIL 8 PM MST THIS EVENING...

...WIND ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS

EVENING...

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A DUST STORM

WARNING...WHICH IS IN EFFECT UNTIL 8 PM MST THIS EVENING. THE

BLOWING DUST ADVISORY IS NO LONGER IN EFFECT. A WIND ADVISORY

REMAINS IN EFFECT UNTIL 11 PM MST THIS EVENING.

* AFFECTED AREA: MARICOPA...AND NORTHWEST PINAL COUNTIES FOR

BOTH DUST AND WINDS.

* LOCATIONS INCLUDE: INTERSTATE 10 BETWEEN PHOENIX AND CASA

GRANDE...HIGHWAY 347 BETWEEN PHOENIX AND MARICOPA...AND INTERSTATE

8 BETWEEN GILA BEND AND CASA GRANDE. OTHER LOCATIONS INCLUDE BUT

ARE NOT LIMITED TO FLORENCE JUNCTION...COOLIDGE AND FLORENCE.

* TIMING: CONTINUING THROUGH 8 PM THIS EVENING.

* WINDS: SUSTAINED SOUTH AND SOUTHWESTERLY WINDS 25 TO 35 MPH GUSTING

TO 45 MPH.

* VISIBILITIES: AREAS REDUCED DOWN TO 3 TO 5 MILES IN BLOWING

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# 13 DUST...LOCALLY BELOW ONE QUARTER MILE IN DUST PRONE LOCATIONS.

* IMPACTS: BLOWING DUST WILL CREATE HAZARDOUS DRIVING CONDITIONS

DUE TO REDUCED VISIBILITIES. STRONG WINDS WILL MAKE VEHICLE

HANDLING MORE DIFFICULT DUE TO CROSS-WINDS...ESPECIALLY FOR

HIGH PROFILE VEHICLES. IN ADDITION...SMALL UNSECURED OBJECTS

AROUND HOMES AND BUSINESSES MAY BECOME AIRBORNE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOTORISTS SHOULD USE EXTRA CAUTION AND BE PREPARED FOR VERY QUICK

AND DRASTIC REDUCTIONS IN VISIBILITY...ESPECIALLY ALONG

INTERSTATES 10 AND 8. IF YOU ENCOUNTER VERY LOW VISIBILITY ON THE

ROADWAY...PULL OFF THE ROAD AS FAR AS POSSIBLE AND PARK...TURN

OFF THE LIGHTS AND KEEP YOUR FOOT OFF THE BRAKE.

A DUST STORM WARNING IS ISSUED WHEN WINDS HAVE GENERATED LARGE AREAS

OF BLOWING DUST OR BLOWING SAND THAT HAVE SUBSTANTIALLY REDUCED

VISIBILITIES...TO 1/4 MILE OR LESS...RESULTING IN HAZARDOUS DRIVING

CONDITIONS IN SOME AREAS. BE READY FOR A SUDDEN DROP IN VISIBILITY TO

NEAR ZERO. USE EXTRA CAUTION AND SLOW DOWN WHILE DRIVING...AS OBJECTS

ON AND NEAR ROADWAYS WILL BE SEEN ONLY AT CLOSE RANGE. IF YOU

ENCOUNTER BLOWING DUST OR BLOWING SAND ON THE ROADWAY OR SEE IT

APPROACHING...PULL OFF THE ROAD AS FAR AS POSSIBLE AND PUT YOUR

VEHICLE IN PARK. TURN THE LIGHTS ALL THE WAY OFF AND KEEP YOUR FOOT

OFF THE BRAKE PEDAL.

A WIND ADVISORY MEANS THAT SUSTAINED WIND SPEEDS OF BETWEEN

30 AND 40 MPH ARE EXPECTED...OR WIND GUSTS OF BETWEEN 40 AND

58 MPH. WINDS THIS STRONG CAN MAKE DRIVING DIFFICULT...ESPECIALLY

FOR HIGH PROFILE VEHICLES. IN AD DITION...STRONG WINDS OVER DESERT

AREAS COULD RESULT IN BRIEFLY LOWERED VISIBILITIES TO WELL UNDER

A MILE AT TIMES IN BLOWING DUST OR BLOWING SAND. USE EXTRA

CAUTION.

AZZ022-050600-

/O.CON.KPSR.DU.Y.0003.000000T0000Z-111105T0300Z/

/O.CON.KPSR.WI.Y.0033.000000T0000Z-111105T0600Z/

NORTHWEST MARICOPA COUNTYINCLUDING THE CITIES OF...BUCKEYE...NEW RIVER...WICKENBURG

207 PM MST FRI NOV 4 2011

...BLOWING DUST ADVISORY REMAINS IN EFFECT UNTIL 8 PM MST THIS

EVENING...

...WIND ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS

EVENING...

A BLOWING DUST ADVISORY REMAINS IN EFFECT UNTIL 8 PM MST THIS

EVENING. A WIND ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS

EVENING.

* AFFECTED AREA: MARICOPA...AND NORTHWEST PINAL COUNTIES FOR

BOTHDUST AND WINDS.

* LOCATIONS INCLUDE: DUST PRONE AREAS NEAR FARM FIELDS AND

CONSTRUCTION SITES WILL BE MOST SUSCEPTIBLE...ESPECIALLY THE

INTERSTATE 10 CORRIDOR THROUGH PINAL COUNTY. OTHERWISE...

STRONG WINDS WILL AFFECT LOCATIONS INCLUDING...BUT NOT

LIMITED TO...GILABEND...TACNA...WELLTON...BUCKEYE... MESA...

PHOENIX...NEW RIVER...WICKENBURG...QUARTZSITE... SALOME...

APACHE JUNCTION...CASA GRANDE...FLORENCE.

* TIMING: CONTINUING THROUGH THIS EVENING.

* WINDS: SUSTAINED SOUTH AND SOUTHWESTERLY WINDS 25 TO 35 MPH

GUSTING 40 TO 50 MPH.

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# 14 * VISIBILITIES: BROAD AREAS REDUCED TO 3 TO 5 MILES...LOCALLY

BELOW ONE MILE.

* IMPACTS: BLOWING DUST WILL CREATE HAZARDOUS DRIVING CONDITIONS

DUE TO REDUCED VISIBILITIES. STRONG WINDS WILL MAKE VEHICLE

HANDLING MORE DIFFICULT DUE TO CROSS-WINDS...ESPECIALLY FOR

HIGH PROFILE VEHICLES. IN ADDITION...SMALL UNSECURED OBJECTS

AROUND HOMES AND BUSINESSES MAY BECOME AIRBORNE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOTORISTS SHOULD USE EXTRA CAUTION AND BE PREPARED FOR VERY QUICK

AND DRASTIC REDUCTIONS IN VISIBILITY...ESPECIALLY ALONG

INTERSTATES 10 AND 8. IF YOU ENCOUNTER VERY LOW VISIBILITY ON THE

ROADWAY...PULL OFF THE ROAD AS FAR AS POSSIBLE AND PARK...TURN

OFF THE LIGHTS AND KEEP YOUR FOOT OFF THE BRAKE.

WWUS75 KPSR 042107

NPWPSR

URGENT - WEATHER MESSAGE

NATIONAL WEATHER SERVICE PHOENIX AZ

207 PM MST FRI NOV 4 2011

AZZ023-027-028-050600-

/O.UPG.KPSR.DU.Y.0003.000000T0000Z-111105T0300Z/

/O.NEW.KPSR.DS.W.0024.111104T2107Z-111105T0300Z/

/O.CON.KPSR.WI.Y.0033.000000T0000Z-111105T0600Z/

GREATER PHOENIX AREA-SOUTHWEST MARICOPA COUNTYNORTHWEST AND NORTH CENTRAL PINAL COUNTYINCLUDING THE CITIES OF...BUCKEYE...MESA...PHOENIX...GILA BEND...

APACHE JUNCTION...CASA GRANDE...FLORENCE

207 PM MST FRI NOV 4 2011

...DUST STORM WARNING IN EFFECT UNTIL 8 PM MST THIS EVENING...

...WIND ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS

EVENING...

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A DUST STORM

WARNING...WHICH IS IN EFFECT UNTIL 8 PM MST THIS EVENING. THE

BLOWING DUST ADVISORY IS NO LONGER IN EFFECT. A WIND ADVISORY

REMAINS IN EFFECT UNTIL 11 PM MST THIS EVENING.

* AFFECTED AREA: MARICOPA...AND NORTHWEST PINAL COUNTIES FOR

BOTH DUST AND WINDS.

* LOCATIONS INCLUDE: INTERSTATE 10 BETWEEN PHOENIX AND CASA

GRANDE...HIGHWAY 347 BETWEEN PHOENIX AND MARICOPA...AND INTERSTATE

8 BETWEEN GILA BEND AND CASA GR ANDE. OTHER LOCATIONS INCLUDE BUT

ARE NOT LIMITED TO FLORENCE JUNCTION...COOLIDGE AND FLORENCE.

* TIMING: CONTINUING THROUGH 8 PM THIS EVENING.

* WINDS: SUSTAINED SOUTH AND SOUTHWESTERLY WINDS 25 TO 35 MPH GUSTING

TO 45 MPH.

* VISIBILITIES: AREAS REDUCED DOWN TO 3 TO 5 MILES IN BLOWING

DUST...LOCALLY BELOW ONE QUARTER MILE IN DUST PRONE LOCATIONS.

* IMPACTS: BLOWING DUST WILL CREATE HAZARDOUS DRIVING CONDITIONS

DUE TO REDUCED VISIBILITIES. STRONG WINDS WILL MAKE VEHICLE

HANDLING MORE DIFFICULT DUE TO CROSS-WINDS...ESPECIALLY FOR

HIGH PROFILE VEHICLES. IN ADDITION...SMALL UNSECURED OBJECTS

AROUND HOMES AND BUSINESSES MAY BECOME AIRBORNE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOTORISTS SHOULD USE EXTRA CAUTION AND BE PREPARED FOR VERY QUICK

AND DRASTIC REDUCTIONS IN VISIBILITY...ESPECIALLY ALONG

INTERSTATES 10 AND 8. IF YOU ENCOUNTER VERY LOW VISIBILITY ON THE

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# 15 ROADWAY...PULL OFF THE ROAD AS FAR AS POSSIBLE AND PARK...TURN

OFF THE LIGHTS AND KEEP YOUR FOOT OFF THE BRAKE.

A DUST STORM WARNING IS ISSUED WHEN WINDS HAVE GENERATED LARGE AREAS

OF BLOWING DUST OR BLOWING SAND THAT HAVE SUBSTANTIALLY REDUCED

VISIBILITIES...TO 1/4 MILE OR LESS...RESULTING IN HAZARDOUS DRIVING

CONDITIONS IN SOME AREAS. BE READY FOR A SUDDEN DROP IN VISIBILITY TO

NEAR ZERO. USE EXTRA CAUTION AND SLOW DOWN WHILE DRIVING...AS OBJECTS

ON AND NEAR ROADWAYS WILL BE SEEN ONLY AT CLOSE RANGE. IF YOU

ENCOUNTER BLOWING DUST OR BLOWING SAND ON THE ROADWAY OR SEE IT

APPROACHING...PULL OFF THE ROAD AS FAR AS POSSIBLE AND PUT YOUR

VEHICLE IN PARK. TURN THE LIGHTS ALL THE WAY OFF AND KEEP YOUR FOOT

OFF THE BRAKE PEDAL.

A WIND ADVISORY MEANS THAT SUSTAINED WIND SPEEDS OF BETWEEN

30 AND 40 MPH ARE EXPECTED...OR WIND GUSTS OF BETWEEN 40 AND

58 MPH. WINDS THIS STRONG CAN MAKE DRIVING DIFFICULT...ESPECIALLY

FOR HIGH PROFILE VEHICLES. IN AD DITION...STRONG WINDS OVER DESERT

AREAS COULD RESULT IN BRIEFLY LOWERED VISIBILITIES TO WELL UNDER

A MILE AT TIMES IN BLOWING DUST OR BLOWING SAND. USE EXTRA

CAUTION.

AZZ022-050600-

/O.CON.KPSR.DU.Y.0003.000000T0000Z-111105T0300Z/

/O.CON.KPSR.WI.Y.0033.000000T0000Z-111105T0600Z/

NORTHWEST MARICOPA COUNTYINCLUDING THE CITIES OF...BUCKEYE...NEW RIVER...WICKENBURG

207 PM MST FRI NOV 4 2011

...BLOWING DUST ADVISORY REMAINS IN EFFECT UNTIL 8 PM MST THIS

EVENING...

...WIND ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS

EVENING...

A BLOWING DUST ADVISORY REMAINS IN EFFECT UNTIL 8 PM MST THIS

EVENING. A WIND ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS

EVENING.

* AFFECTED AREA: MARICOPA...AND NORTHWEST PINAL COUNTIES FOR

BOTHDUST AND WINDS.

* LOCATIONS INCLUDE: DUST PRONE AREAS NEAR FARM FIELDS AND

CONSTRUCTION SITES WILL BE MOST SUSCEPTIBLE...ESPECIALLY THE

INTERSTATE 10 CORRIDOR THROUGH PINAL COUNTY. OTHERWISE...

STRONG WINDS WILL AFFECT LOCATIONS INCLUDING...BUT NOT

LIMITED TO...GILABEND...TACNA...WELLTON...BUCKEYE... MESA...

PHOENIX...NEW RIVER...WICKENBURG...QUARTZSITE... SALOME...

APACHE JUNCTION...CASA GRANDE...FLORENCE.

* TIMING: CONTINUING THROUGH THIS EVENING.

* WINDS: SUSTAINED SOUTH AND SOUTHWESTERLY WINDS 25 TO 35 MPH

GUSTING 40 TO 50 MPH.

* VISIBILITIES: BROAD AREAS REDUCED TO 3 TO 5 MILES...LOCALLY

BELOW ONE MILE.

* IMPACTS: BLOWING DUST WILL CREATE HAZARDOUS DRIVING CONDITIONS

DUE TO REDUCED VISIBILITIES. STRONG WINDS WILL MAKE VEHICLE

HANDLING MORE DIFFICULT DUE TO CROSS-WINDS...ESPECIALLY FOR

HIGH PROFILE VEHICLES. IN ADDITION...SMALL UNSECURED OBJECTS

AROUND HOMES AND BUSINESSES MAY BECOME AIRBORNE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOTORISTS SHOULD USE EXTRA CAUTION AND BE PREPARED FOR VERY QUICK

AND DRASTIC REDUCTIONS IN VISIBILITY...ESPECIALLY ALONG

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# 16 INTERSTATES 10 AND 8. IF YOU ENCOUNTER VERY LOW VISIBILITY ON THE

ROADWAY...PULL OFF THE ROAD AS FAR AS POSSIBLE AND PARK...TURN

OFF THE LIGHTS AND KEEP YOUR FOOT OFF THE BRAKE.

WWUS75 KPSR 050309

NPWPSR

URGENT - WEATHER MESSAGE

NATIONAL WEATHER SERVICE PHOENIX AZ

809 PM MST FRI NOV 4 2011

AZZ023-027-028-050600-

/O.EXP.KPSR.DS.W.0024.000000T0000Z-111105T0300Z/

/O.CON.KPSR.WI.Y.0033.000000T0000Z-111105T0600Z/

GREATER PHOENIX AREA-SOUTHWEST MARICOPA COUNTYNORTHWEST AND NORTH CENTRAL PINAL COUNTYINCLUDING THE CITIES OF...BUCKEYE...MESA...PHOENIX...GILA BEND...

APACHE JUNCTION...CASA GRANDE...FLORENCE

809 PM MST FRI NOV 4 2011

...WIND ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS

EVENING...

...DUST STORM WARNING EXPIRED AT 8 PM MST THIS EVENING...

THE DUST STORM WARNING EXPIRED AT 8 PM MST THIS EVENING. A WIND

ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS EVENING.

* AFFECTED AREA: SOUTHWEST MARICOPA...NORTHWEST PINAL COUNTIES AND

THE GREATER PHOENIX AREA.

* LOCATIONS INCLUDE: GILA BEND...BUCKEYE...MESA...PHOENIX...

APACHE JUNCTION...CASA GRANDE...FLORENCE

* TIMING: CONTINUING THROUGH 11 PM THIS EVENING.

* WINDS: SUSTAINED SOUTH AND SOUTHWESTERLY WINDS 25 TO 35 MPH GUSTING

TO NEAR 45 MPH.

* IMPACTS: STRONG WINDS WILL MAKE VEHICLE HANDLING MORE DIFFICULT

DUE TO CROSS- WINDS... ESPECIALLY FOR HIGH PROFILE VEHICLES. IN

ADDITION...SMALL UNSECURED OBJECTS AROUND HOMES AND BUSINESSES MAY

BECOME AIRBORNE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOTORISTS SHOULD USE EXTRA CAUTION AND BE PREPARED FOR VERY QUICK

AND DRASTIC REDUCTIONS IN VISIBILITY...ESPECIALLY ALONG

INTERSTATES 10 AND 8. IF YOU ENCOUNTER VERY LOW VISIBILITY ON THE

ROADWAY...PULL OFF THE ROAD AS FAR AS POSSIBLE AND PARK...TURN

OFF THE LIGHTS AND KEEP YOUR FOOT OFF THE BRAKE.

AZZ022-023-027-028-050700-

/O.CAN.KPSR.WI.Y.0033.000000T0000Z-111105T0600Z/

NORTHWEST MARICOPA COUNTY-GREATER PHOENIX AREASOUTHWEST MARICOPA COUNTYNORTHWEST AND NORTH CENTRAL PINAL COUNTYINCLUDING THE CITIES OF...BUCKEYE...NEW RIVER...WICKENBURG...

MESA...PHOENIX...GILA BEND...APACHE JUNCTION...CASA GRANDE...

FLORENCE...

1053 PM MST FRI NOV 4 2011

...WIND ADVISORY IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS CANCELLED THE WIND

ADVISORY FOR MARICOPA COUNTY AND NORTHWEST PINAL COUNTY. WINDS ACROSS

MARICOPA COUNTY...NORTHWEST PINAL COUNTY AND THE GREATER PHOENIX AREA

HAVE STAYED BELOW WIND ADVISORY CRITERIA FOR THE MOST PART SINCE 9 PM

# Exceptional Event, Phoenix, November 4, 2011 Appendix D



# 17 AND ARE NOT EXPECTED TO STRENGTHEN SIGNIFICANTLY FOR THE REST OF

TONIGHT. THUS THE WIND ADVISORY HAS BEEN CANCELLED. HOWEVER...IT IS

POSSIBLE THAT WHEN THE COLD FRONT PASSES THROUGH THE AREA LATER

TONIGHT...GUSTY WINDS TO NEAR 40 MPH MAY BRIEFLY OCCUR. OVERALL WINDS

S HOULD REMAIN BELOW 30 MPH FOR THE REST OF TONIGHT.

# Exceptional Event, Phoenix, November 4, 2011 Appendix E



# 1 

# Appendix E:

Affidavit of Public Notice