National Volcanic Ash

Operations Plan for Aviation

*and*

*Support of the ICAO International Airways*

*Volcano Watch*

Federal Coordinator for Meteorological Services

and Supporting Research

8455 Colesville Road, Suite 1500

Silver Spring, Maryland 20910

www.ofcm.gov

301-427-2002

FCM-P35-2006

Washington, DC

March 2007

Preface

National Volcanic Ash Operations Plan for Aviation

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_
\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

**Ms. Victoria Cox Col. Patrick M. Condray**

Vice President Commander

Operations Planning Services Air Force Weather Agency

Federal Aviation Administration United States Air Force

Department of Transportation Department of Defense

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_
\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

**Mr. Dennis H. McCarthy Ms. Linda Gundersen**

Director Chief Scientist for Geology

Office of Climate, Water, and U.S. Geological Survey

Weather Services Department of Interior

National Weather Service

National Oceanic and Atmospheric

Administration

Department of Commerce

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_
\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

**Mr. Richard S. Artz Mr. Michael Matson**

Director (Acting) Director (Acting)

Air Resources Laboratory Office of Satellite Data, Processing,

Office of Oceanic and Atmospheric and Distribution

Research National Environmental Satellite, Data,

National Oceanic and Atmospheric and Information Service

Administration National Oceanic and Atmospheric

Department of Commerce Administration

Department of Commerce

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_
\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

**Dr. Michael Freilich Mr. Lee Siebert**

Director Director

Earth Science Division Global Volcanism Program

Science Mission Directorate Department of Mineral Sciences

National Aeronautics and Space National Museum of Natural History

Administration Smithsonian Institution

# The National Volcanic Ash Operations Plan for Aviation 

# and 

# Support of the ICAO International Airways Volcano Watch

## 

## Table of Contents

## 

Preface iii

Table of Contents vii

1\. Introduction and Background 1-1

1.0 Purpose. 1-1

1.1 Relation to Other Handbooks, Directives, and Manuals 1-1

1.2 Format of this plan 1-2

1.3 Changes to the Plan 1-2

1.4 Agency Procedures and Procedural Changes 1-3

1.5 Questions and Suggestions Regarding the Plan 1-3

2\. Responsibilities of Cooperating Agencies 2-1

2.0 General 2-1

2.1 Responsibilities of Federal Agencies 2-1

2.1.1 Department of Commerce, National Oceanic and Atmospheric
Administration 2-1

2.1.1.1 National Environmental Satellite, Data, and Information Service
2-1

2.1.1.2 National Weather Service 2-1

2.1.1.3 Office of Oceanic and Atmospheric Research 2-1

2.1.2 Department of Defense, U.S. Air Force 2-2

2.1.3 Department of Interior, United States Geological Survey 2-2

2.1.4 Department of Transportation, Federal Aviation Administration 2-2

2.1.5 National Aeronautics and Space Administration 2-2

2.1.6 Smithsonian Institution 2-2

3\. Volcanic Ash Related Products 3-1

3.0 General 3-1

3.1 Observations 3-1

3.1.1 METAR 3-1

3.1.2 PIREP 3-1

3.1.3 VAR 3-1

3.2 Advisories 3-1

3.2.1 VAA 3-1

3.2.2 VAG 3-1

3.3 In-flight Weather Advisories/Warnings 3-2

3.3.1 CWA 3-2

3.3.2 FA 3-2

3.3.3 MIS 3-2

3.3.4 SIGMET (WV) 3-2

3.4 Notices 3-2

3.4.1 NOTAM 3-2

3.4.2 VANA 3-2

3.5 Forecasts 3-3

3.5.1 TAF 3-3

3.5.2 TWEB 3-3

3.6 Model Output 3-3

3.6.1 HYSPLIT 3-3

4\. Operations and Procedures 4-1

4.0 General 4-1

4.1 National Weather Service and National Environmental Satellite Data
and

Information Service 4-1

4.2 Department of Defense, United States Air Force 4-4

4.3 Unites States Geological Survey 4-5

4.4 Federal Aviation Administration 4-7

5\. Observation and Message Report Formats 5.1

5.0 General 5-1

5.1 Area Forecast (FA) 5-1

5.2 Aviation Routine Weather Report (METAR) and

Aviation Special Weather Report (SPECI) 5-3

5.3 Center Weather Advisories (CWA) 5-3

5.4 Meteorological Impact Statement (MIS) 5-3

5.5 Pilot Report (PIREP) 5-4

5.6 SIGMET (WV) 5-4

5.7 Terminal Aerodrome Forecast (TAF) 5-5

5.8 Transcribed Weather Broadcasts (TWEB) 5-5

5.9 Volcanic Ash Advisory (VAA) 5-6

5.10 Volcanic Ash Graphic (VAG) 5-8

5.11 Notice to Airmen (NOTAM) 5-8

5.12 USGS Volcanic Activity Notice for Aviation (VANA) 5-9

5.13 Tentative Volcanic Ash Report (VAR) 5-10

Figures and Tables

Figure 4-1, Principal Exchange and Flow of Information for Volcanic Ash
4-2

Figure 4-2, Areas of Responsibility for Washington D.C. and Anchorage AK
VAACs 4-3

Table 4-1, USGS Aviation Color Codes 4-7

Figure 5-1, Volcanic Ash Graphic 5-8

Figure 5-2, Volcanic Activity Report 5-10

## 

Appendices

A. Back-up Operations

B. Alaska Plan

C. Marianas Plan

D. Transportation and Dispersion Models

E. Acronyms and Terms

F. List of U.S. Volcanoes

## 

Chapter 1

Introduction and Background

**1.0 Purpose.** The National Volcanic Ash Operations Plan for Aviation
*and Support of the International Civil Aviation Organization
International Airways Volcano Watch* (NVOPA) is the national operations
plan in support of observing, tracking, monitoring, forecasting and
reporting volcanic ash in the atmosphere that affects the safety of
flight operations in the United States National Airspace System (NAS).
This document identifies the federal agencies that implement these
actions and describes their responsibilities, procedures/actions, and
message formats.

This document also provides information on how the Federal Aviation
Administration (FAA), the U.S. meteorological authority for aviation
weather, meets its obligations to the International Airways Volcano
Watch (IAVW), sponsored by the International Civil Aviation Organization
(ICAO).

Information on points of contact and useful web sites are provided in
this document. However, readers of this document are encouraged to visit
the current web sites to obtain the most current information on
accessing information. Even though this document establishes the
framework for operations, each agency has the responsibility to document
its internal procedures for implementation of this plan.

1.  **Relation to Other Handbooks, Directives and Manuals**

The NVOPA is consistent with agreements and publications of the World
Meteorological Organization (WMO), ICAO, and civil as well as military
weather services:

**International:**

-   ICAO Annex 3, Meteorological Services for International Air
    Navigation

-   ICAO Annex 10, Aeronautical Communication

-   ICAO Annex 11, Air Traffic Services

-   ICAO Annex 15, Aeronautical Information Services

-   ICAO Handbook on the International Airways Volcano Watch (IAVW):

> Operational Procedures and Contact List (Document 9766)

-   ICAO Manual on Volcanic Ash, Radioactive Material and Toxic Chemical
    Clouds

> (Document 9691)

-   WMO No. 306 -- Manual for Codes

**Domestic:**

-   National Oceanic and Atmospheric Administration's National Weather
    Service

> Directives, series 10-8 Aviation Weather Services, available at
>
> [http://www.nws.noaa.gov/directives]{.underline}.

-   FMH-12, Federal Meteorological Handbook No. 12 - United States
    Meteorological

> Codes and Coding Practices, available at
>
> [http://www.ofcm.gov/fmh12/frontpage.htm]{.underline}

-   FMH-1, Federal Meteorological Handbook No. 1 - Surface Weather
    Observations

> and Reports, available at
> [http://www.ofcm.gov/fmh-1/fmh1.htm.]{.underline}

-   FAA Order 7110.10: Flight Service

-   FAA Order 7110.65: Air Traffic Control

-   FAA Order 7930.2: Notices to AIRMEN

-   FAA Order 7900.5: Surface Weather Observing

-   FAA Aeronautical Information Manual

-   FAA Aeronautical Information Publication

-   FAA AC-00-45E, Aviation Weather Services

-   FAA AC-00-6A, Aviation Weather for Pilots and Flight Operations
    Personnel

-   FAA 8400.10, Handbook for Principal Operating Inspector

    2.  **Format of this plan**

Chapter 2 presents an overview of the responsibilities of the
cooperating agencies in support of the National Volcanic Ash Operations
Plan.

Chapter 3 presents a listing of volcanic ash related operational
products supporting aviation operations.

Chapter 4 discusses general operations and procedures to carry out each
agency's mission related to volcanic ash in support of aviation
operations.

Chapter 5 provides examples of operational products related to volcanic
ash in support of aviation operations.

Appendix A outlines agency backup operational procedures.

Appendix B contains the Alaska Interagency Operating Plan for Volcanic
Ash Episodes.

Appendix C contains the Interagency Operating Plan for Volcanic Ash
Hazards to Aviation in the Pacific Region of the Northern Mariana
Islands.

Appendix D discusses transport and dispersion models.

Appendix E defines the acronyms and terms used in this plan.

Appendix F is a list of U.S. Volcanoes with associated Air-Route-Traffic
Control Centers, Meteorological Watch Offices, and Weather Forecast
Offices

**Number range CHAPTER1.3 Changes to The Handbook**

Changes, additions, deletions, and corrections will be issued, as
necessary. These changes shall be issued only by the Office of the
Federal Coordinator for Meteorology after consultation and coordination
with the Working Group for Volcanic Ash.

**1.4 Agency Procedures and Procedural Changes**

Individual agencies issue their own manuals and directives defining
their procedures which implement the NVOPA. Such manuals shall
complement, not change, the operational procedures contained within this
document.

**1.5 Questions and Suggestions Regarding the NVOPA**

Questions or suggestions about the content/organization of the Plan
should be directed to:

The Office of the Federal Coordinator for Meteorology

8455 Colesville Road, Suite 1500

Silver Spring, MD 20910

Telephone: Commercial (301) 427-2002

FAX (301) 427-2007

DSN 851-1460

# Chapter 2

**Responsibilities of Cooperating Agencies**

**2.0 General.** There are four principal Federal agencies that support
the National Volcanic Ash Operations Plan:

-   Department of Commerce, National Oceanic and Atmospheric

> Administration

-   Department of Defense, United States Air Force

-   Department of Interior, United States Geologic Survey

-   Department of Transportation, Federal Aviation Administration

The National Aeronautics and Space Administration and the Smithsonian
Institution also provide support to the federal agencies through
extending the benefits of earth science research in the areas of
volcanic ash monitoring and tracking. In addition, the Smithsonian
Institution archives information on volcanoes, not only in the United
States, but globally.

**2.1 Responsibilities of Federal Agencies**

**2.1.1 Department of Commerce, National Oceanic and Atmospheric
Administration (NOAA).** NOAA is responsible for the operational
monitoring of the state of the atmosphere, including the presence of
volcanic ash clouds injected into the atmosphere by eruptions. NOAA,
through several of its line organizations, maintains the observational,
analytical, and forecasting capabilities required to estimate the
location and movement of volcanic ash clouds throughout its areas of
responsibility.

> **2.1.1.1 National Environmental Satellite, Data, and Information
> Service (NESDIS).** The Satellite Analysis Branch of NESDIS operates
> the Washington Volcanic Ash Advisory Center (VAAC) in conjunction with
> the National Weather Service, National Centers for Environmental
> Prediction (NCEP).
>
> **2.1.1.2 National Weather Service (NWS).** NOAA's NWS operates the
> Anchorage VAAC and shares the responsibility of operating the
> Washington VAAC with NESDIS. The NWS operates the World Area Forecast
> Center and the World Area Forecast System (WAFS). The NWS operates
> three Meteorological Watch Offices (MWO) located in Anchorage,
> Honolulu, and Kansas City. The NWS also operates numerous Weather
> Forecast Offices (WFO). The NWS also operates Center Weather Service
> Units (CWSU), which support FAA Air Route Traffic Control Centers
> (ARTCC). Through these units, the NWS provides forecasts, advisories,
> and warnings for volcanic ash.
>
> **2.1.1.3 Office of Oceanic and Atmospheric Research.** The Office of
> Oceanic and Atmospheric Research's Air Resources Laboratory conducts
> supporting research to improve dispersion forecast guidance and is
> responsible for transferring updated dispersion modeling capabilities
> to the NWS NCEP. Air Resources Laboratory developed the HYbrid
> Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) dispersion
> model that is used operationally at NCEP.

**2.1.2 Department of Defense, United States Air Force (USAF).** The
USAF through its Air Force Weather Agency (AFWA), Offutt Air Force Base,
Nebraska is the DOD center for volcanic ash advisories and forecasts.
AFWA is responsible for issuing advisory text messages and providing
imagery analysis and forecast visualization products for U.S. forces
worldwide.

**2.1.3 Department of Interior, United States Geological Survey
(USGS).** The USGS has the Federal responsibility to issue disaster
warnings for earthquakes, volcanic eruptions, landslides, or other
geologic catastrophes. The USGS provides eruption warnings and related
notifications based on data and observations collected from extensive
monitoring networks operated by five U.S. volcano observatories
supported primarily by the USGS Volcano Hazards Program.

[]{.mark}

**2.1.4 Department of Transportation, Federal Aviation Administration
(FAA).** FAA is responsible for issuing and disseminating Notices to
Airmen (NOTAM) when notified of precursory volcanic unrest, eruptive
activity, or volcanic ash in the NAS. In addition, the FAA, through its
communication network, disseminates information on volcanic ash to
Airline Operations Centers (AOC), ARTCC, Terminal Radar Approach Control
(TRACON), Flight Services, Towers, System Operations, and other users of
the NAS.

**2.1.5 National Aeronautics and Space Administration (NASA)**. NASA
supports space-based observation and tracking of ash plumes and volcanic
gases through the use of earth-observing research satellites. NASA-built
sensors, carried on both NASA and NOAA satellites, that can characterize
volcanic ash include: the Total Ozone Mapping Spectrometer, the Moderate
Resolution Imaging Spectroradiometer, the Ozone Monitoring Instrument,
and the Tropospheric Emission Spectrometer.

In collaboration with the FAA Aviation Weather Research Program, NASA
provides satellite observations for research on volcanic ash detection.
NASA's research capabilities are transferred to operational forecasting
tools as worked out in agreements with other agencies. Through
competitive solicitations, NASA actively seeks to expand its research
network for satellite observations of volcanic ash activity.

**2.1.6 Smithsonian Institution (SI).** The SI Global Volcanism Program
(GVP), housed within the Mineral Sciences Department of the Natural
History Museum, maintains a database on eruption histories and
characteristics of the world's volcanoes. The GVP also publishes books
and weekly and monthly reports on volcanoes, collects maps, specimens,
photos, and video, and provides handbooks and compilations in support of
understanding Earth's 1,500 volcanoes known to have erupted in the past
10,000 years. The Program has a small staff generally in the Washington,
D.C. office during normal business hours (9am-5pm Monday through Friday,
excluding federal holidays).

Chapter 3

**Volcanic Ash Related Products**

[]{.mark}

**3.0 General.** The following is a list of products that may contain
volcanic ash or volcanic activity information in support of aviation
operations. These products are categorized as: observations, advisories,
inflight weather advisories/warnings, notices, forecasts, and model
output. Examples of these products in their unique message formats are
in Chapter 4.

**3.1 Observations**

**3.1.1 METAR:** METeorological Aerodrome Report. *An international code
(Aviation Routine Weather Report) used for reporting, recording and
transmitting weather observations.*

**3.1.1a SPECI:** *In the
[METAR](http://amsglossary.allenpress.com/glossary/search?id=metar1)
observation program, a [surface
observation](http://amsglossary.allenpress.com/glossary/search?id=surface-observation1)
issued on a non-routine basis as dictated by changing meteorological
conditions.*

Volcanic ash observed at an aerodrome or in the vicinity of an aerodrome
is normally reported in this report**.**

**3.1.2 PIREP:** Pilot Report*.* *A report of inflight weather by an
aircraft pilot or crew member.* Pilots who observe volcanic ash can
report the information in an AIREP or PIREP. When volcanic ash
information is issued in a PIREP the report is referred to as an Urgent
PIREP.

**3.1.2a AIREP:** Aircraft Report. *A report from an aircraft in flight
prepared in conformity with requirements for position, and operational
and/or meteorological reporting.* An AIREP is an inflight evaluation
usually made over areas where weather information is limited or
non-existent (for example, over an ocean).

**3.1.3** **VAR:** Volcanic Activity Report. *A report of volcanic ash
similar in format to a PIREP. However, the VAR may include additional
information on the physical characteristics of the ash.* It may also be
a special AIREP with a supplemental section that describes the ash
cloud. Pilots normally provide VAR information immediately upon
completion of flight operations or during flight debriefings.

**3.2 Advisories**

**3.2.1 VAA:** Volcanic Ash Advisory. *Information issued by a Volcanic
Ash Advisory Center concerning the occurrence or expected occurrence of
volcanic ash that may affect the safety of aircraft operations.* A VAA
is a text message that identifies the volcano, time of eruption,
observed position of the ash cloud, and the forecasted position of the
ash. The VAA is not to be used as a warning message.

**3.2.2 VAG:** Volcanic Ash Graphic. *A graphical depiction of the
Volcanic Ash Advisory (VAA).*

**3.3 Inflight Weather Advisories/Warnings**

**3.3.1 CWA:** Center Weather Advisory*. The CWA is a 0-2 hour (valid up
to 2 hours after issuance)* *aviation weather warning* primarily used by
pilots to anticipate and avoid adverse weather conditions in the
en-route and terminal environments.

**3.3.2** **FA:** Area Forecast. *Forecast issued by the MWO which
describes weather conditions specific to aviation interests.* Each FA
contains a synopsis, forecast, and outlook portion. FA issuance times
and forecast periods vary somewhat due to customer requirements. The FA
will describe, in abbreviated language, specified en-route weather
phenomena below FL450. FAs are produced for the following areas:

-   Six (6) geographical areas in the Continental United States. (CONUS)
    and adjacent coastal waters

-   Hawaiian Islands and coastal waters (out to 40 nm from the
    coastline)

-   State of Alaska and coastal waters of Alaska.

**3.3.3** **MIS:** Meteorological Impact Statement*. An unscheduled flow
control and flight operations planning forecast. It is a 2-12 hour
(valid up to 12 hours after issuance) briefing and forecast product at
ARTCC, Air Traffic Control System Command Center (ATCSCC), TRACON, and
the Air Traffic Control Towers (ATCT) responsible for making
flow-control type decisions.* The MIS details weather conditions
expected to adversely impact air traffic flow in the CWSU area of
responsibility.

**3.3.4 SIGMET (WV):** SIGnificant METeorological Information. *SIGMET
is a brief description of the occurrence and/or expected occurrence of
specified en-route weather phenomena that may affect the safety of all
aircraft operations.* It is issued by the MWO. A SIGMET message is a
warning of the observed occurrence or expected occurrence of a volcanic
ash cloud.

**3.4 Notices**

**3.4.1 NOTAM:** Notice to Airmen. *A notice containing information
concerning the establishment, condition or change in any aeronautical
facility, service, procedure or hazard, the timely knowledge of which is
essential to personnel concerned with flight operations.* Information
related to the pre-eruption or eruptive stage of a volcano can be
reported in a NOTAM. Included in a NOTAM is the color code, which is
provided by a Volcano Observatory (VO). The NOTAM Office normally issues
a NOTAM based on information as provided by the ARTCC.

## 3.4.2 VANA: Volcano Activity Notice for Aviation. *A short message in structured format issued by a USGS Volcanic Observatory to describe volcanic activity to the aviation sector, highlighting ash-plume information and including the aviation color code.* The VANA is provided to the appropriate ARTCC, MWO, and VAAC in support of the issuance of NOTAM, VAA, VAG, and SIGMET, as well as to AFWA to support DOD advisories. 

**3.5 Forecasts**

**3.5.1 TAF:** Terminal Aerodrome Forecast. *A forecast of
meteorological conditions significant to aviation at an airport location
(location within 5 nm of center of the airports runway complex).* These
forecasts are issued by NWS and DOD every 6 hours with amendments issued
as needed.

**3.5.2 TWEB:** Transcribed Weather Enroute Broadcast. *A NWS prepared
text forecast for aviation for specific identified routes and local
vicinities. The TWEB route is defined as a 50 nm wide corridor between
anchor points. The TWEB local vicinity forecast is a 50 nm wide radius
around a particular location.* The TWEB includes specific weather
information necessary for aviation for a period of 12 hours. Local
vicinity forecasts may cover several airports.

**3.6 Model Output**

**3.6.1 HYSPLIT:** The HYbrid Single-Particle Lagrangian Integrated
Trajectory model. *HYSPLIT is the official model used by NOAA to
forecast the transport and dispersion of the ash cloud.*

**Chapter 4**

**Operations and Procedures**

**4.0 General.** Every effort has been made to standardize terminology,
adopt common definitions, and adjust criteria to a common base; however,
each agency has different operational criteria that must be met.
Standardization is used wherever possible in advisories, forecasts and
warnings; however, each agency retains the right to specify the criteria
needed to carry out its mission. Figure 4-1 shows the principal exchange
and flow of products and information for volcanic ash.

**4.1 National Weather Service and National Environmental Satellite,
Data, and Information Service**

**4.1.1 General.** The NWS and NESDIS have the responsibility for
providing warnings or advisories for the CONUS, coastal waters, oceanic
flight information regions (FIR), and Alaska. This responsibility is
fulfilled by the NCEP/Aviation Weather Center, WFO, CWSU, MWO, VAAC, and
World Area Forecast Center. The NWS also has responsibility to
disseminate reports, warnings and advisories.

**4.1.2 Operations and Procedures.** The Anchorage and Washington VAAC
are staffed 24 hours per day, 7 days per week to provide guidance and
support to MWO and the aviation community (Fig. 4-2). Duty
meteorologists are tasked to monitor remote sensing data, PIREPs, and
reports from the VO and aviation community on a continuous basis. The
VAAC are also tasked to run the ash dispersion models, determine current
and forecast area extent of the ash, and produce VAA and VAG for its
customers. The MWO are responsible for issuing the volcanic ash SIGMET
(WV).

> **4.1.2.1 Volcanic Ash Advisory Centers.** The Washington and
> Anchorage VAAC each issue VAA and VAG as support and guidance to the
> MWO for issuance of WV.

Upon detection of volcanic ash in satellite imagery or upon receipt of a
report of volcanic activity or ash from a bonafide source, the VAAC
will:

-   Review/analyze satellite images and other data sets of the area for
    the time of the event to confirm the presence of a volcanic ash
    cloud and, if possible, its extent.

-   Prepare and issue advisory information (VAA/VAG) on the observed and
    forecasted location of the volcanic ash cloud, in both text and
    graphical format, for transmission to the MWO and ARTCC.

![](media/image1.jpeg){width="3.90625in" height="2.3229166666666665in"}

**Figure 4-2**. The area of responsibility for the Washington, D.C.
(red)

and Anchorage, AK (blue) VAACs.

-   As needed, initiate the NOAA volcanic ash dispersion model (HYSPLIT;
    see appendix D) in order to provide guidance in preparing the
    VAA/VAG.

The VAAC will monitor subsequent satellite information to assist in
tracking the movement of ash clouds, updating of advisory information to
the MWO, ARTCC, and AOC at intervals of at least 6 hours, or sooner,
until the ash cloud is no longer identifiable from satellite imagery or
no further reports of volcanic ash or further eruptions have been
received.

> **4.1.2.2 Meteorological Watch Offices.** There are three MWOs in the
> United States: Anchorage, Alaska; Honolulu, Hawaii; and Kansas City,
> Missouri. The Kansas City MWO is also known as the Aviation Weather
> Center and the Anchorage MWO is known as the Alaska Aviation Weather
> Unit. The MWO is responsible for the issuance of a SIGMET for volcanic
> ash. Upon receipt of information concerning a volcanic eruption and/or
> the existence of a volcanic ash cloud, the MWO:

-   Issues a SIGMET;

-   Amends the FA, if appropriate;

-   Notifies the VAAC; and

-   Advises the ARTCC/Flight Service Station (FSS) whether or not ash is
    identifiable on satellite and provide any follow-up information
    concerning both horizontal and vertical extent of the ash plume.

In addition to the SIGMET, the MWO will amend the Area Forecast if
applicable to include reference to the SIGMET.

The Kansas City MWO supports:

-   20 ARTCC in the conterminous United States including coastal waters

-   New York, Miami, Houston, San Juan Oceanic FIRs

-   Oakland Oceanic FIR north of 30 degrees N latitude, and the portion
    east of 140 degrees west longitude, which is between the equator and
    30 degrees north latitude

The Honolulu MWO is responsible for the Oakland Oceanic FIR south of 30
degrees north, and between 140 west and 130 east longitude.

The Anchorage MWO supports the Anchorage FIR.

Current SIGMET information can be found at:
http://aviationweather.noaa.gov/

> **4.1.2.3 Weather Forecast Offices.** The WFO are responsible for
> issuing the TAF for select locations. These forecasts cover a five (5)
> nautical mile radius around the center point of the runway complex and
> they are issued every 6 hours with amendments as needed. Under the NWS
> directive 10-5 series, the WFO also issue Ashfall Advisories and under
> the 10-3 series, the WFO issue marine weather statements that include
> ash information.
>
> **4.1.2.4 Center Weather Service Units.** The CWSU prepares the Center
> Weather Advisory (CWA) supporting the ARTCC in the NAS. The CWSU
> provides advisories of hazardous weather conditions for airborne
> aircraft. The role of the CWSU during a volcanic eruption will depend
> somewhat on the situation and flow of information. When an initial
> report of an eruption is received at the ARTCC, the CWSU meteorologist
> or designee will enter the report as an URGENT PIREP (UUA). The CWSU
> meteorologist will then call the MWO to relay the volcano information.

**4.2 Department of Defense/United States Air Force**

**4.2.1 General.** The U.S. Air Force through its Air Force Weather
Agency (AFWA), Offutt Air Force Base, Nebraska, is the DOD center for
volcanic ash alerts and forecasts. AFWA is responsible for issuing a
specialized set of advisory text, imagery analysis and forecast
visualization graphics products for U.S. Forces worldwide. It also
provides a backup for the Washington VAAC in case of disruptions to
ensure continuity of operations.

**4.2.2 Operations and Procedures.**

> **4.2.2.1 AFWA.** The Meteorological Satellite Applications Branch at
> Headquarters AFWA issues volcanic ash guidance products for the DOD.
> These products include text advisories incorporating information from
> NOAA VAA and SIGMET and USGS VANA. These products also include
> forecast ash trajectory outputs in both animation and static panel
> format utilizing tailored interactive graphic visualizations of Puff
> model trajectory forecasts and satellite imagery analysis.

AFWA will notify the appropriate VAAC if it detects an ash plume in
imagery surveillance, or other observational data, and has not received
a VAA message. AFWA will also notify the VAAC if imagery analysis or
other data suggests different conclusions than indicated in the VAA.

When functioning as the backup for the Washington VAAC, AFWA will issue
a VAA and produce a Volcanic Ash Forecast Transport and Dispersion model
format graphic look-alike based on Puff. The VAG is not provided in
backup mode.

**4.3 United States Geological Survey**

**4.3.1 General.** The USGS gathers and interprets operational data from
its observatory monitoring networks and any other relevant sources and
provides notices of significant precursory unrest and the onset and
cessation of eruptive activity. The USGS has Volcanic Observatories
located as follows:

-   The Hawaiian Volcano Observatory on Hawaii Island monitors volcanoes
    on the islands of Hawaii and Maui and shares monitoring in the
    Northern Mariana Island with other VO.

-   The Cascades Volcano Observatory (CVO) in Vancouver, Washington,
    monitors the Cascade Range volcanoes in Washington, Oregon, and
    Northern California. CVO partners with the University of Washington
    to conduct seismic monitoring in the Cascades. CVO also shares
    monitoring in the Northern Mariana Islands.

-   The Alaska Volcano Observatory (AVO), monitors Alaskan volcanoes.
    USGS partners with the University of Alaska Fairbanks Geophysical
    Institute and State of Alaska Division of Geological and Geophysical
    Surveys in the operation of AVO.

-   The Long Valley Observatory monitors the Long Valley caldera in
    California, shares monitoring in the Marianas region, and supports
    CVO with monitoring in California.

-   The Yellowstone Volcano Observatory, a collaborative effort of the
    USGS Volcano Hazards Program, the University of Utah, and
    Yellowstone National Park, monitors the Yellowstone caldera.

**4.3.2 Operations and Procedures**

Each VO is headed by a Scientist-in-Charge who is responsible for the
overall monitoring effort and for determining alert levels for volcanoes
monitored by a particular observatory. VO are not staffed 24/7 on a
routine basis, although duty scientists carry beepers and phones to
receive automatic notification when data levels recorded on key
geophysical sensors exceed pre-set thresholds. VO operate 24/7 watches
only during periods of extreme unrest or eruption.

> **4.3.2.1 Volcano Observatories.** The principal role of the VO in
> support of aviation is to alert ARTCC, MWO, and VAAC of significant
> precursory volcanic unrest or eruptive activity, including information
> about ash plumes. Information provided by the VO is used by FAA in the
> preparation of a NOTAM on the status of the volcano, by MWO in
> issuance of WV, and by VAAC in issuance of VAA and VAG.
>
> For the aviation sector, in accord with recommended ICAO procedures,
> VO issue color-coded alert levels -- Green, Yellow, Orange, and Red --
> focused on ash hazards (see Table 4-1). Color codes reflect conditions
> at the volcano and depend upon monitoring data and interpretation of
> changing phenomena. A telephone "call down" is implemented when alert
> levels are raised or lowered in the following order of priority:

1.  The appropriate ARTCC/FIR Operations Manager

2.  The appropriate MWO

3.  Washington or Anchorage VAAC

4.  AFWA

5.  The appropriate WFO

> **4.3.2.2 Volcanic Ash Notice for Aviation.** The assigned aviation
> color code is incorporated into the text of a VANA (format in section
> 5.12). VANA are issued when color codes change (up or down) or within
> a color code when significant change occurs in volcanic activity. VANA
> are provided to the appropriate ARTCC, MWO, and VAAC by telephone
> calls and faxes on commercial communication networks and by emails
> over the public Internet.
>
> **4.3.2.3** To supplement the VANA, VO also provide on the publicly
> accessible website (http://volcanoes.usgs.gov): information in
> addition to what is incorporated into a NOTAM and information about
> low-level unrest (color code Yellow) that may not warrant issuance of
> a NOTAM.

+--------+-------------------------------------------------------------+
| **AV   |                                                             |
| IATION |                                                             |
| COLOR  |                                                             |
| C      |                                                             |
| ODES** |                                                             |
+--------+-------------------------------------------------------------+
| **G    | Volcano is in normal, non-eruptive state.                   |
| REEN** |                                                             |
|        | *or, after a change from a higher level*:                   |
|        |                                                             |
|        | Volcanic activity considered to have ceased, and volcano    |
|        | reverted to its normal, non-eruptive state.                 |
+--------+-------------------------------------------------------------+
| **YE   | Volcano is exhibiting signs of elevated unrest above known  |
| LLOW** | background levels.                                          |
|        |                                                             |
|        | *or, after a change from higher level*:                     |
|        |                                                             |
|        | Volcanic activity has decreased significantly but continues |
|        | to be closely monitored for possible renewed increase.      |
+--------+-------------------------------------------------------------+
| **OR   | Volcano is exhibiting heightened unrest with increased      |
| ANGE** | likelihood of eruption,                                     |
|        |                                                             |
|        | *or*,                                                       |
|        |                                                             |
|        | Volcanic eruption is underway with no or minor ash emission |
|        | *\[specify ash-plume height if possible\].*                 |
+--------+-------------------------------------------------------------+
| *      | Eruption is forecast to be imminent with significant        |
| *RED** | emission of ash into the atmosphere likely.                 |
|        |                                                             |
|        | *or,*                                                       |
|        |                                                             |
|        | Eruption is underway with significant emission of ash into  |
|        | the atmosphere *\[specify ash-plume height if possible\]*.  |
+--------+-------------------------------------------------------------+

Table 4-1. A description of USGS aviation color coded alert levels.

**4.4 Federal Aviation Administration**

**4.4.1 General.** The FAA has the responsibility to ensure that all
provisions of meteorological services are provided to users of the NAS
which includes the dissemination and distribution of observations,
forecasts, and warning messages that pertain to volcanic ash. In
addition, the FAA is responsible for issuing NOTAM on the status of a
volcano during pre-eruption and eruption phases.

**4.4.2 Operations and Procedures**

## 4.4.2.1 Air Route Traffic Control Center. The FAA ARTCC is responsible for all activities within its designated airspace and for determining if a hazard(s) will affect its operations. The Operations Manager, upon receipt of a PIREP or other valid source of volcanic activity, should first verify that information with the respective VO (see appendix F). When an Operations Manager receives volcanic information listed in section 3.1 directly from a VO, the following procedures are recommended *(note: local facility orders may supersede these procedures)*:

> A\) Notify the following key personnel:

-   Center Weather Service Unit Meteorologist, or designee.

```{=html}
<!-- -->
```
-   Traffic Management Unit Officer/Weather Coordinator.

-   FAA Regional Operations Center.

-   ARTCC Facility Manager.

-   Watch Supervisor of the Automated Flight Service Station (AFSS)/FSS
    nearest the volcanic activity.

-   Watch Supervisors of any affected TRACON and Tower.

-   Systems Operations Center Maintenance Control Center.

-   Air Traffic Control System Command Center.

```{=html}
<!-- -->
```
-   Military Base Operations (if appropriate).

> B\) Issue a Flight Data Center (FDC) NOTAM, using the information
> received from the VO, in the prescribed format listed in Chapter 5,
> Paragraph 5.11. (Note: A Navigational Aid (NAVAID)/Radial/ Distance
> will need to be determined from the latitude/longitude and included in
> all NOTAMs*.*) Forward this NOTAM to the U.S. NOTAM Office (USNOF) via
> the NOTAM Entry System, Fax, or Commercial Phone for
> national/international dissemination. USNOF will disseminate FDC NOTAM
> nationally (and internationally if appropriate). NOTAM information is
> available to the public at: https://pilotweb.nas.faa.gov
>
> C\) The Operations Supervisor Controller In Charge/Controller In
> Charge (CIC) will ensure that:

-   PIREP are solicited by controllers.

```{=html}
<!-- -->
```
-   NOTAM and PIREP information is disseminated to controllers on duty
    in a timely manner.

```{=html}
<!-- -->
```
-   Forward Urgent PIREP for volcanic ash to CWSU/Weather Coordinator
    for dissemination.

> D\) Traffic Management personnel will:

-   Review affected areas for required traffic management initiatives
    and coordinate with the ATCSCC and all affected facilities.

```{=html}
<!-- -->
```
-   Controllers will:

    -   Provide to aircraft the most current information available
        (SIGMET, CWA, MIS, PIREP) concerning the ash cloud position,
        altitude and movement.

    ```{=html}
    <!-- -->
    ```
    -   Suggest headings and re-routes around known ash or possible ash
        areas.

    -   Assist Visual Flight Rules aircraft to the extent possible in
        avoiding ash cloud areas.

    -   Solicit PIREP and forward to Operations Supervisor.

[]{.mark}

## 4.4.2.2 Terminal Radar Approach Control/Tower.

> A\) The TRACON/Tower Watch Supervisor/CIC, upon receipt of volcanic
> information from the ARTCC, will:

-   Ensure NOTAM and PIREP information is disseminated to controllers on
    duty in a timely manner.

```{=html}
<!-- -->
```
-   Ensure PIREP are solicited by controllers.

```{=html}
<!-- -->
```
-   Forward PIREP to ARTCC CWSU/Weather Coordinator or AFSS/FSS for
    dissemination.

B\) TRACON/Tower controllers are to:

-   Provide SIGMET, CWA, PIREP concerning the ash cloud position,
    altitude and movement to flight crews.

```{=html}
<!-- -->
```
-   Suggest headings and re-routes around known ash or possible ash
    areas.

```{=html}
<!-- -->
```
-   Assist VFR aircraft to the extent possible in avoiding ash cloud
    areas.

```{=html}
<!-- -->
```
-   Solicit PIREP and forward to Watch Supervisor.

## 4.4.2.3 Automated Flight Service Station/Flight Service Station

> A\) The AFSS/FSS Watch Supervisor/CIC, upon receipt of volcanic
> information and PIREPs from an ARTCC or a TRACON/Tower will ensure:

-   NOTAM and PIREP information is disseminated to specialists on duty
    in a timely manner.

```{=html}
<!-- -->
```
-   PIREPS are solicited by specialists at the Inflight, Flight Watch,
    and Pre-flight positions.

```{=html}
<!-- -->
```
-   National dissemination of PIREPS (UA and UUA) using existing
    platforms.

> B\) The AFSS/FSS Watch Supervisor/CIC, upon receipt of volcanic
> activity or ash cloud PIREPs from an aircraft will:

-   Ensure that the PIREP information is forwarded to the ARTCC
    Operations Manager

C\) AFSS/FSS specialist will:

-   Provide the most current information available (SIGMET, CWA, PIREP,
    NOTAM) concerning volcanic activity/ash cloud position, altitude and
    movement in preflight/inflight briefings.

```{=html}
<!-- -->
```
-   Solicit PIREPS and input PIREP information into existing platforms
    for dissemination.

```{=html}
<!-- -->
```
-   Broadcast Volcanic Ash SIGMETs, CWA's and PIREPS using the Hazardous
    Inflight Weather Advisory Service, Tactical Information Broadcast
    System, and Inflight Broadcast procedures.

```{=html}
<!-- -->
```
-   Pass PIREP information received from aircraft on volcanic activity
    or ash clouds to the AFSS Watch Supervisor.

## 

## 4.4.2.4 Air Traffic Control System Command Center. Upon receipt of VAA from the Washington or Anchorage VAAC, the ATCSCC relays the advisory to designated recipients (Traffic Management Units, airlines, etc.) through e-mail distribution and also displays the advisory on the ATCSCC web site in the advisories database: http://www.fly.faa.gov/adv/advADB.jsp

**Chapter 5**

**Observation and Message Report Formats**

**5.0 General.** This section provides examples, current as of the date
of this plan, of observations, forecasts, and products which contain
volcanic ash or volcanic activity information in support of aviation.
The basic definitions of these were provided in Chapter 2. Refer to
official agency or international documents for further information.
Volcanic ash wording is highlighted in gray.

**5.1 Area Forecast (FA).** FA are issued for the CONUS, Alaska, and
Hawaii. FA are issued three times a day in the CONUS and four (4) times
a day in Alaska and Hawaii, and amended as necessary. The forecast valid
period for the CONUS and Hawaii is 12 hours with an outlook period from
12 to 18 hours. In Alaska, the FA is valid for 12 hours and the outlook
is valid from 12 to 30 hours. Example FA are shown for CONUS, Hawaii,
and Alaska:

[CONUS FA Example]{.underline}

FAUS46 KKCI 281804

FA6W

SFOC FA 281804 AMD

SYNOPSIS AND VFR CLDS/WX

SYNOPSIS VALID UNTIL 290500

CLDS/WX VALID UNTIL 282300\...OTLK VALID 282300-290500

WA OR CA AND CSTL WTRS

.

SEE AIRMET SIERRA FOR IFR CONDS AND MTN OBSCN.

TS IMPLY SEV OR GTR TURB SEV ICE LLWS AND IFR CONDS.

NON MSL HGTS DENOTED BY AGL OR CIG.

.

SYNOPSIS\...MT ST HELENS ERUPTED AT 1230 UTC. SEE LATEST SIGMET BRAVO
SERIES FOR DETAILS. OTHW ALF..11Z RDG OVR GREAT BASIN TO SRN CA. TROF
OVR GULF OF AK. LGT SW FLOW WA THRU NRN CA WITH LGT AND VRBL WNDS SRN
CA. BY 05Z TROF MOVG SEWD TO CSTL WTRS OF WA THRU NRN CA WITH RDG OVR

UT/WRN AZ. MOD SW FLOW WA/OR. SFC..WK TROF CNTRL WA THRU SW ORE

WITH WK TROF INTR CA. HIGH PRES OVR NRN PAC CSTL WTRS. AMS STBL

AND DRY EXC FOR CSTL STRATUS. BY 05Z CDFNT DVLPG NERN WA THRU S

CNTRL ORE WITH GUSTY WLY LOW LVL WNDS OVR WA.

.

WA CASCDS WWD \...UPDT

CASCDS\...SKC. VIS 3-5SM [VA]{.mark}. OTLK\...MVFR [VA]{.mark}.

CSTLN\...BKN-OVC010 TOP 015. VIS 3-5SM BR. 20Z SCT010.

OTLK\...MVFR CIG.

INLAND\...SCT010. VIS 3-5SM BR. 18Z SKC. OTLK\...VFR.

.

WA E OF CASCDS

SKC. OCNL VIS 3SM FU/LCL LWR ALF. OTLK\...VFR.

[Alaska FA Example]{.underline}

FAAK58 PAWU 071953

FA8W

ANCC FA 071945

AK SRN HLF EXCP SE AK\...

.

AIRMETS VALID UNTIL 080200

TS IMPLY PSBL SEV OR GREATER TURB SEV ICE LLWS AND IFR CONDS.

NON MSL HEIGHTS NOTED BY AGL OR CIG.

.

UNIMAK PASS TO ADAK AJ\...VALID UNTIL 080800

\...CLOUDS/WX\...

\*\*\*SIGMET\*\*\*INDIA 1 VALID 071813/080013

ANCHORAGE FIR.

[VOLCANIC ASH FROM CLEVELAND VOLCANO (N5250 W16957) POSSIBLE ERUPTION OF
CLEVELAND VOLCANO AT 071000 UTC. ASH BOUNDED BY N5400W16500 -
N5330W16200 -- N5230W16300 -- N5300W16600 -- N5400W16500. ASH TOPS AT
FL150. ASH MOV ESE 40 KT. ASH VISIBLE IN STLT IMAGERY.]{.mark}

\*\*\*AIRMET TURB/LLWS\*\*\*MOD TURB BLW 120. OCNL MOD TURB FL290-FL370.

LLWS POTENTIAL DUE TO STG LOW LVL WINDS. NC\...

\*\*\*AIRMET MT OBSC\*\*\*MTS OCNL OBSC IN CLOUDS AND PCPN. NC\... OTRW

SCT020 BKN-SCT060 BKN-SCT100 TOPS 120. OCNL BKN020. WDLY SCT

VIS 5SM -SHRA. SFC WIND W 20G30 KTS.

OTLK VALID 080800-090200 MVFR CIG SHRA WIND.

\...TURB\...

\*\*\*AIRMET TURB\*\*\*OCNL MOD TURB BLW 040. NC\...

\...ICE AND FZLVL\...

NIL SIG. FZLVL 030.

[Hawaii FA Example]{.underline}

FAHW31 PHFO 281530

FA0HI

HNLC FA 281540

SYNOPSIS AND VFR CLD/WX

SYNOPSIS VALID UNTIL 291000

CLD/WX VALID UNTIL 290400\...OUTLOOK VALID 290400-291000

.

SEE AIRMET SIERRA FOR IFR CLD AND MT OBSC.

TS IMPLY SEV OR GREATER TURB SEV ICE LOW LEVEL WS AND IFR COND.

NON MSL HGT DENOTED BY AGL OR CEILING.

.

SYNOPSIS\...KILAEUA VOLCANO ERUPTED AT 1350 UTC PRODUCING A SMALL AMOUNT
OF ASH. SEE NOVEMBER SIGMET SERIES FOR DETAILS. A SURFACE TROUGH HAS
MOVED WEST OF THE ISLANDS\...AND TRADE WINDS WILL GRADUALLY STRENGTHEN
IN THE OFFSHORE WATERS THROUGH THE EARLY PART OF THE WEEK.

.

BIG ISLAND MT.

SCT050 TEMPO BKN050 TOPS 120 ISOL BKN030 LCL VIS 6SM [VA]{.mark}. 21Z

SCT040 BKN-OVC050 TOPS 150 TEMPO BKN030 -SHRA ISOL VIS 1-2SM -SHRA

BR. OUTLOOK\...MVFR CEILING SHRA.

.

BIG ISLAND LOWER SLOPES\...COAST\...AND ADJ WATERS.

SCT050 TEMPO SCT025 BKN040 TOPS 080 -SHRA ISOL BKN030 VIS 5SM -SHRA

BR. 21Z SCT025 SCT-BKN050 TOPS 100 TEMPO BKN020 -SHRA ISOL BKN015

VIS 2-3SM -SHRA BR. OUTLOOK\...VFR.

.

REST OF AREA.

SCT050 ISOL BKN040 TOPS 060 -SHRA. OUTLOOK\...VFR.

## 

**5.2 Aviation Routine Weather Report (METAR) and Aviation Special
Weather Report (SPECI).**

[METAR Example]{.underline}

METAR PANC 182150 010006KT [6SM VA]{.mark} FEW040 FEW100 SCT250 02/M09
RMK AO2 SLP 996 T00171089

METAR KPDX 271955Z 31010KT 10SM CLR 30/12 A2990 RMK AO2 SLP124 [MT
ST]{.mark}

[HELENS VOLCANO 50 MILES NNE ERUPTED 271915 SMALL ASH CLOUD
EXTENDING]{.mark}

[TO APRX 15000 FEET MOVING E]{.mark} T03000122

METAR PGUA 241355Z 29005KT [7SM VA]{.mark} SCT020 SCT100 BKN250 26/26
A2981

RMK SLP084

[SPECI Example]{.underline}

SPECI KPDX 271926Z 32005KT 10SM CLR 29/13 A2991 RMK AO2 [MT ST
HELENS]{.mark}

[VOLCANO 50 MILES NNE ERUPTED 271915 SMALL ASH CLOUD EXTENDING
TO]{.mark}

[APRX 15000 FEET MOVING E]{.mark}

**5.3 Center Weather Advisories (CWA).** An aviation weather warning for
conditions which either meet or approach national Inflight advisory
criteria, or will adversely impact the safe flow of air traffic within
the ARTCC area of responsibility.

[Center Weather Advisory Example]{.underline}

ZAN1 UCWA 210025

ZAN UCWA 101 VALID UNTIL 210225

COOK INLET

[POSSIBLE ERUPTION OF MT. AUGUSTINE AT 21/0025 UTC. ASH TOPS ESTIMATED
TO FL350 BASED ON GROUND OBSERVER REPORT. ASH MOVG NE AT 35 KTS.]{.mark}
A SIGMET WILL BE ISSUED SHORTLY.

JO AUG 05

**5.4 Meteorological Impact Statement (MIS).** A MIS is an unscheduled
flow control and flight operations planning forecast. It is a forecast
and briefing product for personnel at ARTCC, ATCSCC, TRACON, and ATCT
responsible for making flow control-type decisions. The MIS is valid up
to 12 hours after issuance time, detailing weather conditions expected
to adversely impact air traffic flow in the CWSU area of responsibility.
This includes being valid immediately for existing conditions when CWSU
operations begin or for rapidly deteriorating conditions, or being valid
up to two hours in advance of expected conditions. A MIS may be tailored
to meet the unique requirements of the host ARTCC.

[MIS Example]{.underline}

ZAN MIS 01 VALID 092200-100900\
\...FOR ATC PLANNING PURPOSES ONLY\...\
GUSTY SE WINDS WILL RESUSPEND [VA]{.mark} CAUSING VSBY TO LOWER TO BLW 1
MILE. CONDS TO IMPV AFT 06Z.

**5.5 Pilot Report (PIREP).** Pilots can report the occurrence of
volcanic ash in a PIREP as an Urgent PIREP (UAA).

[Urgent PIREP Examples]{.underline}

PGSN UUA /OV SN355070/TM 2315/FLDURC/TP B757/RM [TOP OF ASH
CLOUD]{.mark}

[OVER ANATAHAN VOLCANO APPROXIMATELY 15000 FT DRIFTING]{.mark}

[EAST]{.mark}

OLM UUA /OV CLS /TM 1850 /FL 090 /TP BE35 /WV 31005KT /TB NEG
/[RM]{.mark}

[MT ST HELENS PLUME TO SE AT 090]{.mark}

PDX UUA /OV BTG020040/TM 1917/FL085/TP C210/[RM ASH CLOUD 115 TO]{.mark}

[SFC]{.mark}

CDB UUA /OV VENIAMINOF VOLCANO (5610N 15923W)/TM 2231/FLUNKN/TP

SF34/RM [PUFFS OF SMOKE 1000 FT ABV RIM OR APPROX FL092]{.mark} (ZAN)

**5.6 SIGMET (WV).** WV are brief descriptions of the occurrence and/or
expected occurrence of specified en-route weather phenomena (e.g.,
volcanic ash) which may affect the safety of all aircraft operations.

[SIGMET Example (over land]{.underline})

(SIGMETs issued for the CONUS use VORs not latitude longitude as
prescribed in Annex 3)

WVUS06 KKCI 021430

WV6N

SFON WS 021430

SIGMET NOVEMBER 2 VALID UNTIL 021830

WA OR

[FROM 50S SEA TO 40WSW YKM TO 40E PDX TO PDX TO 50S SEA]{.mark}

[VOLCANIC ASH BLW 140. ASH MOVG SLOLY SE.]{.mark} RPRTD BY ACFT. CONDS

ENDG 1830Z.

WVUS06 KKCI 090356

SFOY WS 090350

SIGMET YANKEE 4 VALID UNTIL 090750

WA

[FROM 40WSW GEG TO 30NNE PDT TO 30NNE PDX TO 50S SEA TO 40WSW
GEG]{.mark}

[VOLCANIC ASH RPRTD SFC UP THROUGH FL360 DRIFTING ENEWD AT
40KTS.]{.mark}

RPRTD BY ACFT. CONDS CONTG BYD 0750Z.

[SIGMET Example (over Oceanic FIR)]{.underline}

WVNT13 KKCI 251500

WSVA0M

TJZS SIGMET MIKE 5 VALID 251500/252100 KKCI-

SAN JUAN FIR [VOLCANIC ASH FROM SOUFRIERE HILLS 1643N06211W. VA]{.mark}

[FCST BLW FL090. WI 15 NM EITHER SIDE OF LINE 1644N06420W]{.mark}

[1641N06300W. ASH MOV W 20KT.]{.mark} NC. BASED ON LATEST WASHINGTON
VAAC

ADVISORY. OUTLOOK 26/0300 SFC/090 14NM LN BTN 1657N06445W-

1657N06350W-1643N06216W.

[SIGMET Example (from Meteorological Watch Office, Honolulu,
HI)]{.underline}

WVPA06 PHFO 282046

WSVPAS

KZOA SIGMET SIERRA 452 VALID 282050/290250 PHFO-

OAKLAND OCEANIC FIR. [VOLCANIC ASH FROM ANATAHAN VOLCANO OBS BY]{.mark}

[SATELLITE AT 282002Z SFC/150 WITHIN AREA BOUNDED BY N1644 E14641
-]{.mark}

[N1615 E14644 - N1618 E14544 - N1621 E14543 - N1644 E14641 MOVING E
15]{.mark}

[KNOTS.]{.mark} FCST 290200Z [VA CLD APRX SFC/150 WITHIN AREA BOUNDED BY
N1621]{.mark}

[E14543 - N1549 E14645 - N1525 E14637 - N1621 E1454. OTLK 290800Z
VA]{.mark}

[CLD APRX SFC/FL N1620 E14541 - N1518 E14647 - N1457 E14634 -
N1620]{.mark}

[E1454. ANATAHAN VOLCANO LOCATED AT N1621 E14540.]{.mark}

[SIGMET Example (from Meteorological Watch Office, Anchorage,
AK)]{.underline}

WVANCI WS 071813

PAZA SIGMET INDIA 1 VALID 071813/080013

ANCHORAGE FIR.

[VOLCANIC ASH FROM CLEVELAND VOLCANO (N5250 W16957) POSSIBLE ERUPTION OF
CLEVELAND VOLCANO AT 071000 UTC. ASH BOUNDED BY N5400W16500 -
N5330W16200 -- N5230W16300 -- N5300W16600 -- N5400W16500. ASH TOPS AT
FL150. ASH MOV ESE 40 KT. ASH VISIBLE IN STLT IMAGERY.]{.mark}

ERW OCT 05

**5.7 Terminal Aerodrome Forecasts (TAF).** A TAF is the expected
meteorological conditions significant to aviation at an airport
(terminal) for a specified time period, usually 24 hours. The U.S.
definition of a terminal is the area within five (5) statute miles of
the center of an airport\'s runway complex. TAFs are covered in the
National Weather Service Instruction (NWSI) 10-813, Terminal Aerodrome
Forecasts.

[TAF Example]{.underline}

TAF PAHO 171738Z 171818 04006KT P6SM SCT100

FM0000 35003KT [6SM VA]{.mark} SCT100 BKN250

FM1400 00000KT P6SM BKN100

**5.8 Transcribed Weather Broadcasts (TWEB).** A transcribed weather
broadcast (TWEB), is a NWS-prepared text product for the CONUS, which
including a synopsis and forecast for more than 200 routes and local
vicinities. A TWEB is valid for a 12-hour period, for routes and local
vicinities describing specific information on sustained surface winds
(25 knots or greater), visibility, weather and obstructions to vision,
sky conditions (coverage and ceiling/cloud heights), mountain
obscuration, and non-convective low-level wind shear. The routes are
50-nautical mile (NM)-wide corridors (25 NM either side) along a line
connecting the anchor points of the route, and a 25 NM radius
semi-circle around the end points. The anchor and end points are TAF
locations. TWEBs are covered in NWSI 10-805, Transcribed Weather
Broadcasts.

[TWEB Example]{.underline}

TWB357\
357 TWEB 140214 KBLI-KPAE-KSEA. ALL HGTS MSL EXC CIGS. [P6SM VA]{.mark}
SCT010 BKN100...10Z P6SM SKC.

**5.9 Volcanic Ash Advisory (VAA).** The VAA is a text message that
identifies the volcano, time of eruption, and observed and forecast
position of the ash and ash cloud. Examples from the Washington and
Anchorage VAACs are provided. In addition, a "Quick" VAA is an advisory
stating that the VAAC has received information on the possible eruption
of a particular volcano. The VAAC will gather further information and a
more detailed and full VAA will be provided as soon as possible. An
example of the "Quick" VAA is also provided.

## [VAA Example (Washington VAAC)]{.underline}

## 

FVXX21 KNES 251440

[VOLCANIC ASH ADVISORY]{.mark}

ISSUED: 2005AUG25/1440Z VAAC: WASHINGTON

VOLCANO: ST. HELENS 1201-05

LOCATION: N4612 W12211 AREA: US-WASHINGTON

SUMMIT ELEVATION: 8363 FT (2549 M)

ADVISORY NUMBER: 2005/018

INFORMATION SOURCE: GOES-10. USGS. JRO CAMERA.

AFWA. PORTLAND WFO.

ERUPTION DETAILS: RESUSPENDED ASH

OBS ASH DATE/TIME: 25/1415Z

OBS ASH CLOUD: SFC/FL080 10NM WIDE LINE BETWEEN

N4635 W12310 - N4612 W12211. VA IS MOVING NW 5-10

KNOTS.

FCST ASH CLOUD +6H: 25/2030Z SFC/FL080 N4632 W12243

\- N4619 W12204 - N4613 W12201 - N4610 W12210 -

N4623 W12252 - N4632 W12243

FCST ASH CLOUD +12H: 26/0230Z NO VA EXP.

FCST ASH CLOUD +18H: 26/0830Z NO VA EXP.

REMARKS: MSH CAMERA AND G-10 VISIBLE IMAGERY SHOW

A MODERATELY DENSE PLUME OF ASH TO THE NW OF THE

VOLCANO ABOUT 30 NMI. THIS IS NOT RELATED TO ANY

ERUPTION BUT IS DUE TO WINDS AT THE CRATER

RESUSPENDING ASH AND BLOWING IT NW. PLUME HEIGHT

DOES NOT EXCEED THE CRATER RIM. \...GALLINA

NEXT ADVISORY: WILL BE ISSUED BY 2005AUG25/2045Z

NNNN

## 

## [VAA Example (Anchorage VAAC)]{.underline}

FVAK21 PAWU 071841

[VOLCANIC ASH ADVISORY]{.mark}

ISSUED: 2005OCT07/1840Z VAAC: ANCHORAGE

VOLCANO: CLEVELAND 1101-24

LOCATION: N5250 W16957 AREA: ALEUTIAN ISLANDS ALASKA

SUMMIT ELEVATION: 5674 FT (1730 M)

ADVISORY NUMBER: 2005/001

INFORMATION SOURCE: AVO.

AVIATION COLOR CODE: ORANGE

ERUPTION DETAILS: BRIEF ERUPTION FROM 07/1000Z TO 07/1100Z

OBS ASH DATA/TIME: 07/1800Z

OBS ASH CLOUD: SFC/FL150 N5400 W16500 - N5530 W16200 - N5230 W16300 -
N5300 W16600 - N5400 W16500. VA IS MOVING ESE AT 40 KNOTS.

FCST ASH CLOUD +6HR: 08/0000Z SFC/FL150 N5330 W15800 - N5300 W15530 -
N513000 W15600 - N5200 W15900 - N5330 W15800

FCST ASH CLOUD +12HR: 08/0600Z SFC/FL150 N5300 W15100 - N5200 W14830 -
N5030 W15000 - N5130 W15200 - N5300 W15100

FCST ASH CLOUD +18HR: 08/1200Z NO ASH EXP.

REMARKS: NONE. \...NAME

NEXT ADVISORY: WILL BE ISSUED BY 2005OCT08/0040Z

NNNN

["Quick" VAA Example (Washington VAAC)]{.underline}

FVXX20 KNES 161400

[VOLCANIC ASH ADVISORY]{.mark}

ISSUED: 2006MAR16/1400Z VAAC: WASHINGTON

VOLCANO: SANTA MARIA

LOCATION: N1445 W09133 AREA: GUATEMALA

SUMMIT ELEVATION: 12375 FT (3772 M)

ADVISORY NUMBER: 2006/050

INFORMATION SOURCE: NOT AVBL

ERUPTION DETAILS: NOT AVBL

REMARKS: WE HAVE RECEIVED INFORMATION SUGGESTING A

POSSIBLE VA EMISSION. WE WILL GATHER FURTHER

INFORMATION AND ISSUE A FULL ADVISORY AS SOON AS

POSSIBLE.

NEXT ADVISORY: AS SOON AS POSSIBLE

**5.10 Volcanic Ash Graphic (VAG).** The VAG (Figure 5-1) is a graphical
description of the text Volcanic Ash Advisory (VAA). The VAG can either
by a single panel product or a 4 panel product (separate panel for each
time step t+0, t+6, t+12, and t+18). The following is an example of a
VAG:

![](media/image2.jpeg){width="5.995833333333334in"
height="4.995833333333334in"}

## 5.11 Notice to Airmen (NOTAM). The NOTAM examples are provided in order to ensure correct formats are followed. 

[Increased Seismic Activity NOTAM Example]{.underline}

!FDC xx/xxx (ARTCC id) (state code).. SEISMIC ACTIVITY ADVISORY
EFFECTIVE IMMEDIATELY UNTIL FURTHER NOTICE FOR (name) VOLCANO,
(latitude/longitude), AND THE (name) /id/ VORTAC or VOR/DME (number)
DEGREE RADIAL AT (distance) NAUTICAL MILES. (name) VOLCANO OBSERVATORY
HAS REPORTED INCREASED SEISMIC ACTIVITY IN THE VICINITY OF (name)
VOLCANO WHICH INDICATES THE POSSIBILITY OF A VOLCANIC ERUPTION. AIRCRAFT
SHOULD REMAIN ALERT FOR POSSIBLE ERUPTIONS, STEAM, OR [ASH]{.mark}
CLOUDS AND REPORT ANY SIGHTINGS TO ATC IMMEDIATELY. AVIATION ALERT COLOR
CODE (orange or red) IS IN EFFECT. CONTACT (name) ARTCC, (telephone
number), FOR ADDITIONAL INFORMATION.

[FDC 4 CFR section 91.137(a)(1) Flight Restriction NOTAM
Format]{.underline}

!FDC xx/xxx (ARTCC id) (state code).. FLIGHT RESTRICTIONS
(location:town/city) EFFECTIVE (immediately or yyyy-mm-dd-hhhh) UTC
UNTIL (further notice or yyyy-mm-dd-hhhh) UTC. PURSUANT TO 14 CFR
SECTION 91.137(a)(1) TEMPORARY FLIGHT RESTRICTIONS ARE IN EFFECT FOR
VOLCANIC ERUPTION/ACTIVITY. ONLY RELIEF AIRCRAFT OPERATIONS UNDER THE
DIRECTION OF (agency in charge) ARE AUTHORIZED IN THE AIRSPACE AT AND
BELOW \_\_\_\_\_\_ FEET (AGL or MSL) WITHIN A \_\_\_\_\_\_
STATUTE/NAUTICAL MILE RADIUS OF (latitude/longitude) AND THE (name of
navaid/id) VORTAC (or) VOR/DME \_\_\_\_\_ DEGREE RADIAL AT \_\_\_\_\_
NAUTICAL MILES. AVIATION ALERT COLOR CODE (orange or red) IS IN EFFECT.
PILOTS ARE ADVISED TO EXERCISE EXTREME CAUTION WHEN OPERATING NEAR THIS
RESTRICTED AREA PARTICULARLY WHILE DOWNWIND FROM THE VOLCANO. (Agency
name, telephone number, and/or frequency) IS IN CHARGE OF THE OPERATION.
(Designated ATC facility, (phone number) or the Air Traffic Organization
(ATO) System Operations Control Center (SOSC), 202-267-3333), IS THE FAA
COORDINATION FACILITY.

## [Volcanic Ash NOTAM Format]{.underline}

!FDC xx/xxx (ARTCC id) (state code) VOLCANIC ADVISORY FOR (name) VOLCANO
(state code),(latitude/longitude), and the (name) /id/ VORTAC or VOR/DME
(number)DEGREE RADIAL AT (distance) NAUTICAL MILES EFFECTIVE IMMEDIATELY
UNTIL FURTHER NOTICE. (name) VOLCANO HAS BEEN IN AN ACTIVE STATE.
HAZARDOUS EMISSIONS OF VOLCANIC [ASH]{.mark} HAVE INTERMITTENTLY
COMPLICATED AIR TRAVEL IN THE AREA. ANY IMPACT ON AIRCRAFT OPERATIONS IS
DESCRIBED IN CURRENT SIGMET, CWA, OR PIREP INFORMATION. AIRCRAFT SHOULD
REMAIN ALERT FOR POSSIBLE [ASH]{.mark} CLOUDS AND REPORT ANY SIGHTINGS
TO ATC. AIRCRAFT OPERATORS SHOULD CONTINUALLY EVALUATE OPERATIONS TO AND
FROM (location). AVIATION ALERT COLOR CODE (orange or red) IS IN EFFECT.
FLIGHT INTO VOLCANIC ASH MAY CAUSE ENGINE DAMAGE/FAILURE AND ABRASION
DAMAGE TO AIRFRAME AND WINDSHIELD SURFACES. ANY AIR CARRIERS, INCLUDING
FOREIGN AIR CARRIERS THAT OBSERVE OR EXPERIENCE ANY DIFFICULTIES
RESULTING FROM AN ENCOUNTER WITH VOLCANIC [ASH]{.mark}, PLEASE NOTIFY
ATC IMMEDIATELY IN ACCORDANCE WITH FAR 121.561 AND ICAO,ANNEX 3,
PARAGRAPH 5.4 (SPECIAL AIRCRAFT OPERATIONS), AND ANNEX 6 PARAGRAPH 4.4.3
(HAZARDOUS FLIGHT CONDITIONS). CONTACT (name) ARTCC, (phone number), FOR
ADDITIONAL INFORMATION.

**5.12 USGS Volcanic Activity Notice for Aviation (VANA).** Suggested
format for a VANA. A VANA is issued by a VO when a color code changes
(up or down) or within a color-code level when significant change in
volcanic behavior occurs.

**(1)** **USGS VOLCANIC ACTIVITY NOTICE FOR AVIATION**

**(2)** **Issued:** Universal (Z) date and time (YYYYMMDD/HHMMZ).

**(3)** **Volcano:** Name and number (per Smithsonian database at

http://www.volcano.si.edu/world/ ("Summary List")

**(4)** **Current Aviation Color Code:**

**(5)** **Previous Aviation Color Code:**

**(6) Source:** Name of Volcano Observatory

**(7**) **Notice Number:** Year/number (YYYY/xxx)

**(8) Volcano Location:** Latitude and longitude in degrees and minutes
(e.g., N1621E14540)

**(9) Area:** Regional descriptor (e.g., Cook Inlet, Alaska, USA)

**(10) Summit Elevation:** nnnn FT (nnnn M)

**(11) Volcanic Activity Summary:** Free text, limited to 10 lines. If
known, specify time

and duration of eruptive activity.

**(12)** **Observed Volcanic Cloud Height:** nnnn M (nnnnn FT) above
summit or AMSL

(specify which). Give source of height data (ground observer, pilot
report, radar, etc.).

"NIL" if no ash cloud produced.

**(13) Other Volcanic Cloud information:** Free text, limited to 10
lines, with comments on

cloud characteristics (ash content, direction of movement, etc.).
Specify if cloud

height is obscured or suspected to be higher than what can be observed
clearly.

"NIL" if no ash cloud produced.

**(14) Remarks:** Free text, limited to 10 lines. Include comments on
seismic and other

monitoring data, observatory actions, volcano's previous activity, etc.

**(15) Contacts:** Names, phone numbers (voice and fax), email addresses

**(16) Next Notice:** Will be issued when conditions at the volcano
warrant changing the aviation

color code or when a significant volcanic event occurs at this alert
level. Or, indicate if

final notice for an event.

![](media/image3.png){width="3.6569444444444446in" height="4.75in"}

**5.13 Volcanic Activity Report (VAR).** The VAR form (Figure 5-2) is
tentative. It is undergoing international review and is expected to be
endorsed by the ICAO Council in the first quarter of 2007 then become
applicable in November 2007.