Natural Disaster Survey Report

Ft. Smith and Van Buren, Arkansas, 

Tornado of April 21, 1996

U.S. Department of Commerce

National Oceanic and Atmospheric Administration

National Weather Service

Silver Spring, Maryland
Natural Disaster Survey Report

Ft. Smith and Van Buren, Arkansas,

Tornado of April 21, 1996

December 1996

U.S. Department of Commerce

Mickey Kantor, Secretary

National Oceanic and Atmospheric Administration

Dr. D. James Baker, Administrator

National Weather Service

Dr. Elbert W. Friday, Jr., Assistant Administrator
iii

PREFACE

As the National Weather Service moves forward in our modernization efforts we have

made tremendous strides in improving our warning process to provide longer lead

times and more precise delineation of warning areas. It would be easy to assume that

the enhancements offered by new technologieshave led effortlessly to these forecast

improvements. As this tragic event has shown us, however, technology is not the only

key to success. Our success results from the dedicated efforts of motivated personnel

using improved technological tools and a clear understanding of the scientific basis of

each meteorological event to provide the best possible service to the American public. 

Only if advances in observing and display technology are matched by ongoing training

in and understanding of the underlying causal science will we provide the full benefits

of modernization to the public.

Elbert W. Friday, Jr.

Assistant Administrator 

 For Weather Services

December 1996
iv

FOREWORD

This report on the Ft. Smith and Van Buren, Arkansas, tornado of April 21, 1996 was prepared by

a NWS Disaster Survey Team (DST). The DST conducted the field survey over a period of four

days. The initial work was conducted through investigations and interviews in Tulsa, Oklahoma,

Ft. Smith, Van Buren and Little Rock, Arkansas, from April 24 through April 26, 1996. Additional

interviews were conducted in Ft. Smith on April 30, 1996. 

To create this report, the DST collected information from the components of the Storm Prediction

Center located in Kansas City; the Weather Service Office in Ft. Smith; the NEXRAD Weather

Service Forecast Offices in Tulsa and Little Rock; the National Climatic Data Center in Asheville,

North Carolina; and the WSR-88D Operational Support Facility in Norman, Oklahoma. The DST

also gained valuable insight and information through interviews and conversations with volunteer

amateur radio operators, members of the print and broadcast media in Ft. Smith, the Ft. Smith

City Administrator, and survivors in the areas devastated by the tornado. Officials of the Ft.

Smith and Van Buren Police Departments were particularly helpful in ensuring the DST had

complete access to the damaged areas. This information was used to develop an assessment

of the performance and effectiveness of the NWS offices involved in this event. It was used to

examine their relationships to local governments and to the media, and the paths that warnings

took from the forecast office to the public. This report summarizes the available information,

presents findings on the performance of the participating NWS offices, and makes

recommendations to enhance or improve the performance of these and other NWS offices. 

In response to widespread interest in the findings of the DST, the production of this report

departed from the standard practice. The DST reconvened in Kansas City, Missouri, the week of

May 6, 1996, to conduct additional interviews, to assemble the collected information, and to

develop the basis for a preliminary report consisting of an Executive Summary, a set of Facts,

Findings, and Recommendations, and a collection of substantiating documentation. A

Preliminary Report was released to the Arkansas delegation to the U.S. Congress, to local

government officials in Ft. Smith and Van Buren, and to the media on May 21, 1996. By

releasing this report in preliminary form in May, the NWS chose to provide these findings as early

as possible to allow the improvements in operations and services found in the recommendations

to begin. Having achieved this critical goal of the Disaster Survey Report, this final version of

the report will not spend significant resources on drafting and finalizing a detailed description of

the facts provided. Continuing investigation did result in additional clarification to Finding 4.1

and the addition of Recommendation 4.2. 

The DST wishes to thank the NWS employees, volunteer amateur radio operators, and local

government officials interviewed for their frank discussions. We also extend our heartfelt

appreciation and sympathy to the survivors of this event who shared their stories, their pain, and

their hopes with us.
v

TABLE OF CONTENTS

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii

Executive Summary ..........................................................v

Disaster Survey Team Members . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii

Acronyms and Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix

Facts, Findings, and Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi

Chapter 1: Description and Impact of Event ........................................1

Chapter 2: Meteorological Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Chapter 3: Observational Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Chapter 4: Warnings, Forecasts, and Guidance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Chapter 5: Preparedness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Chapter 6: Communications and Dissemination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Chapter 7: User Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Appendix A: Fujita Tornado Intensity Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

Appendix B: Overall Performance Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

Appendix C: Referenced Forecasts and Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
vi

EXECUTIVE SUMMARY

On Sunday, April 21, 1996, a severe weather outbreak across the Southern Plains

produced a number of supercell thunderstorms and tornadoes which developed in

northwest Texas and southwest Oklahoma. This severe weather then tracked east

northeast across much of south central and northeast Oklahoma and northwest

Arkansas during the late afternoon and evening hours.

This report, while providing a general overview of the severe weather event, focuses on

the Fort Smith metropolitan area of northwest Arkansas, where a strong tornado

caused extensive property damage, two fatalities, and more than forty injuries.

The tornado touched down on the west side of downtown Fort Smith at 11:12 p.m. CDT

on the evening of April 21, 1996. After causing extensive damage to a number of

historic buildings in the downtown area, the tornado moved northeast through an

industrial area and then into a residential area on the north side of Fort Smith. The

tornado then crossed the Arkansas River and moved into a residential area on the west

side of Van Buren, Arkansas, and continued moving northeast through a more sparsely

populated area.

Two fatalities occurred in the residential area on the north side of Fort Smith. Two

children died in frame houses heavily damaged by the tornado. Numerous injuries

occurred in the residential areas of both Fort Smith and Van Buren, where the tornado

substantially damaged approximately 1,800 homes. Two additional fatalities occurred

in St. Paul, Madison County, Arkansas, approximately 50 miles northeast of Ft. Smith

as the parent thunderstorm produced another tornado in that area almost one hour

after the storm moved through Ft. Smith.

The tornado was estimated to be approximately one-half-mile wide with a path length of

approximately seven miles. The F3 tornado, as defined by the Fujita Tornado Intensity

Scale, was estimated to have wind speeds of nearly 200 mph. At this intensity, roofs

and walls were torn off well-constructed houses, train cars were overturned, and

automobiles were lifted off the ground.

The severe weather outbreak was forecast in advance. The National Weather Service

(NWS) Storm Prediction Center (SPC) in Kansas City, Missouri, identified the potential

for severe weather in the Oklahoma/Arkansas area nearly two days prior to the onset of

the outbreak. Severe weather outlooks were issued by the NEXRAD Weather Service

Forecast Office (NWSFO) in Tulsa earlier on the 21st based on information from the

SPC. The SPC issued a Tornado Watch which included the Ft. Smith and St. Paul

areas three hours prior to the tornado striking Ft. Smith and Van Buren. 
vii

A Severe Thunderstorm Warning, issued 16 minutes prior to the onset of the tornado,

identified the potential for tornadoes. The warning specified “Hail to the size of

quarters and gusts to 70 mph can be expected in the warned area. A Tornado Watch is

also in effect for the warned area. Remember, severe thunderstorms can and

occasionally do produce tornadoes with little or no advance warning.” When a Tornado

Warning was issued four minutes prior to the onset of the tornado, a power loss at the 

Ft. Smith Police Department caused a failure of the primary communications method

with Ft. Smith officials, depriving them of critical input to their decision to sound the

Civil Defense sirens. As a result, the sirens were not sounded. The same storm

system then moved northeast and the Tulsa NWSFO issued a Tornado Warning for the

St. Paul area 25 minutes before the tornado struck that community.

The Tulsa NWSFO detected and tracked the supercell thunderstorm which produced

the Ft. Smith/Van Buren tornado using the Weather Surveillance Radar 1988 Doppler

(WSR-88D) radar. In addition, the severe weather spotter network servicing the Ft.

Smith area and immediately adjacent counties in Oklahoma provided timely reports to

NWSFO Tulsa via amateur radio.

 At issue is why a Severe Thunderstorm Warning was issued for a storm that had a

known tornadic history. The NWS Disaster Survey Team found that the Tulsa warning

team perceived that the storm, while still dangerous, was decreasing in tornadic

potential and, therefore, issued a Severe Thunderstorm Warning. This perception was

influenced by several factors: 

1) The warning team relied most heavily on a velocity product which had

provided clear definition of tornadic potential of the storm in its passage from

McAlester through Stigler, Oklahoma, resulting in tornado warnings with 30

minute lead time. However, in the three six-minute radar observation cycles just

prior to the tornado warning decision, this product provided ambiguous

information which was most easily interpreted as a decrease in the intensity of

the mesocyclone.

2) The warning team did not clarify tornado location inconsistencies between

spotter reports and radar signatures.

3) The warning team put too much importance on the lack of damage reports

from areas over which the storm passed in making their decision. 

While the National Weather Service and the Ft. Smith community cannot alter the

amount of destruction caused by a storm of this magnitude, working together as

partners will minimize human casualties. The low loss of life in this storm may be

attributed to a combination of factors. Preparedness activities conducted by the Ft.

Smith and Tulsa NWS offices and their partners in the local government and private

sector contributed to the public’s knowledge of life-saving actions. Early, widespread

media coverage of the weather outlook and the storm’s potential threat to the Ft. Smith

metropolitan area prompted individuals to seek safe shelter. The response of the local 

hospital and several senior citizen homes to the pending severe weather threat was

commendable. These facilities implemented their disaster action plans well in advance
viii

of the tornado’s arrival in Ft. Smith.

There were numerous watches, forecasts and warnings issued throughout the

afternoon and evening of the event. These products alerted citizens throughout

eastern Oklahoma and western Arkansas to the potential of severe weather including

the threat of tornadoes prior to the actual tornado warning for the Ft. Smith and Van

Buren areas. This, coupled with the responsiveness of the media and a generally

aware public, without doubt, saved lives. However, there were some important lessons

learned from the Ft. Smith event which are applicable to the entire NWS. Greater

emphasis on interpretation of a representative suite of available Doppler products,

vigorous questioning and clarification of spotter information, and a reduced

dependence on damage reports should enhance the warning decision making process.
ix

DISASTER SURVEY TEAM MEMBERS

Team Leader James D. Belville, Director, WSR-88D Operational Support Facility,

NWS

Technical Leader Robin A. Radlein, AWIPS Focal Point, Technology & Forecast

Systems Core, Office of Meteorology, NWS

Steve Schurr, Meteorologist-in-Charge, NWS Office, Hastings,

Nebraska

Melvin “Mac” McLaughlin, Chief, Meteorological Services Division,

Southern Region Headquarters, NWS

Randee S. Exler, Chief, NWS Public Affairs, NOAA

Technical Support John Ferree, Instructor, Operations Training Branch, WSR-88D

Operational Support Facility, NWS 
x

ACRONYMS AND ABBREVIATIONS

AP Associated Press

ASOS Automated Surface Observing System

AWIPS Advanced Weather Interactive Processing System

CAPE Convective Available Potential Energy

CDT Central Daylight Savings Time

CST Central Standard Time

CWA county warning areas

DST Disaster Survey Team

EBS Emergency Broadcast System

EHI Energy Helicity Index

EMWIN Emergency Manager Weather Information Network 

EOC Emergency Operations Center

FAR False Alarm Ratio

FCC Federal Communications Commission

FEMA Federal Emergency Management Agency

kg kilogram

kt knots (nautical miles per hour)

J Joules

LETS Law Enforcement Telecommunications System

LI Lifted Index

m meters

MAR Modernization and Associated Restructuring

mb millibars

MIC Meteorologist-in-Charge

mi miles (statute)

mph miles (statute) per hour

NAWAS National Warning System

NEXRAD Next Generation Radar

NGM Nested Grid Model

nm nautical miles

NOAA National Oceanic and Atmospheric Administration

NOW Short Term Forecast (Nowcast)

NWR NOAA Weather Radio

NWS National Weather Service 

NWSFO NEXRAD Weather Service Forecast Office

NWSO NEXRAD Weather Service Office

NWWS NOAA Weather Wire Service

OUN Norman, OK, NWSFO

POD Probability of Detection

PUP Principal User Processor

s second

SFD State Forecast Discussion

SGF Springfield, MO, NWSO
xi

SPC Storm Prediction Center

SPS Special Weather Statement

SRH Storm Relative Helicity

SRM Storm Relative Velocity Map

SVR Severe Thunderstorm Warning

SVS Severe Weather Statement

SWEAT Severe Weather Threat

TOR Tornado Warning

UTC Universal Coordinated Time (Greenwich Mean Time)

Vr Rotational Velocity

WCM Warning Coordination Meteorologist

WSO Weather Service Office (without NEXRAD)

WSR-74C Weather Surveillance Radar-1974 (C-Band)

WSR-88D Weather Surveillance Radar-1988 Doppler
xii

FACTS, FINDINGS, AND RECOMMENDATIONS

A. Description and Impact of the Event

A1. Fact

The tornado that struck Ft. Smith and Van Buren, Arkansas, the night of April 21, 1996,

was one of several produced by a long-lived supercell. This supercell was one of

many that occurred from southwest Oklahoma and northwest Texas northeast into

northwest Arkansas and southwest Missouri during this event.

A2. Fact 

The destructive tornado which struck Ft. Smith and Van Buren, Arkansas, resulted in

the death of two young children and between 40 and 50 injuries. 

A3. Fact

The Ft. Smith/Van Buren tornado damaged several historical buildings in Ft. Smith and

damaged or destroyed approximately 1800 homes located in a half-mile-wide, sevenmile-long swath extending from the downtown section of Ft. Smith northeast into

residential areas of Van Buren. The destructive path also caused widespread damage

to warehouses, industrial buildings, and a new waste water treatment plant in Ft. Smith. 

A4. Fact

The same supercell which spawned the Ft. Smith/Van Buren tornado subsequently

generated another tornado, killing a father and son who took shelter in a car in St. Paul,

Arkansas, nearly 50 miles northeast of the Ft. Smith area.

B. Meteorological Analysis

B1. Fact 

Many of the meteorological parameters typically required for development of severe

thunderstorms were present over Oklahoma and northwest Arkansas on the afternoon

and evening of April 21, 1996. 

B2. Fact

Thunderstorms began mid-afternoon on Sunday, April 21, over west Oklahoma and

northwestern Texas. The severe thunderstorm that eventually produced the Ft.

Smith/Van Buren tornado formed in south central Oklahoma around 6 p.m. Its

movement to the east northeast, to the right of the mean steering flow, carried it across

the Ft. Smith area shortly after 11 p.m. The storm continued moving across northwest

Arkansas for two more hours before weakening. 
 The path of the storm which spawned the Ft. Smith/Van Buren tornado remained outside of the area of 1

degraded radar coverage to the south of Ft. Smith as identified in the Secretary’s Report to Congress on

the Adequacy of Weather Services Under National Weather Service Modernization for 32 Areas of

Concern . 

xiii

C. Observational Evaluation

C1. Fact

The Tulsa WSR-88D detected this supercell thunderstorm throughout its lifecycle, most

of which was in the Tulsa County Warning Area (CWA). The base velocity and storm

relative velocity products indicated a strong mesocyclone almost continuously from

McAlester, Oklahoma, through Ft. Smith/Van Buren, Arkansas, and northeast into the

St. Paul area. Both the Tulsa WSR-88D radar, located 89 miles northwest of Ft. 1

Smith, and the Little Rock WSR-88D radar, located 126 miles east, showed a well

defined velocity couplet identifying the area of mesocyclone rotation as the storm

moved across the Ft. Smith area.

Finding 1.1

The one-minute and five-minute Ft. Smith Automated Surface Observing System

(ASOS) data, which were not available in real-time, would have provided detailed

surface observation data for the Ft. Smith area. When integrated with the WSR88D data, additional information concerning the increased inflow into the

mesocyclone, as well as strong pressure falls as the storm approached, would

have been available to the forecasters in Tulsa.

Recommendation 1.1

The ability to access and display detailed ASOS data integrated with radar and

other data sources needs to be incorporated in the Advanced Weather

Information Processing System (AWIPS).

C2. Fact

The Tulsa and Ft. Smith NWS offices both received a continuous flow of reports from

severe storm spotters via amateur radio. All reports received by the Ft. Smith office

were called to the Tulsa office in a timely manner.

D. Warnings, Forecasts, and Guidance

D1. Fact

The Severe Weather Outlooks issued by the Storm Prediction Center identified the

potential for severe weather in the northwest Arkansas area nearly two days prior to the

development of this outbreak. Subsequent outlooks continued to emphasize the

potential for development of tornadoes.
xiv

Finding 2.1

The Tulsa NEXRAD Weather Service Forecast Office (NWSFO) issued Public

Information Statements at 6 a.m. and 1 p.m. on April 21, 1996, regarding the

potential severe weather threat for the day, including the possibility of

tornadoes. These statements, while containing valuable information, were quite

lengthy, limiting their utility to the media.

Recommendation 2.1

Public Information Statements are designed to be used by the media to alert the

populace to a predicted weather event. Information contained in such statements

should be concise and easy to use. 

D2. Fact

The Storm Prediction Center issued Tornado Watch Number 219 which included the Ft.

Smith area three hours prior to the occurrence of the tornado.

D3. Fact

Tulsa issued a Severe Thunderstorm Warning for Pittsburg County, Oklahoma, at 8:20

p.m. This was upgraded to a Tornado Warning at 8:57 p.m with a 30 minute lead time. 

A tornado was reported in northeast Pittsburg County at 9:27 p.m. by McAlester,

Oklahoma, Emergency Management. Tornado Warnings were subsequently issued

for Haskell, north LaFlore, and south Sequoyah Counties in Oklahoma as the storm

continued moving east northeast.

D4. Fact

The short term forecast is regularly available through commercial vendors, NOAA

Weather Radio (NWR) and the NOAA Weather Wire. These are routinely displayed by

the Weather Channel. A short term forecast issued by the Tulsa NWSFO at 10:33

p.m. advised, “If this storm holds together, it will affect the Ft. Smith, Arkansas, area

after 11 pm. In addition to tornadoes, this storm is capable of producing hail up to golf

ball size and winds up to 70 mph.”

D5. Fact

At 10:54 p.m. the Tulsa NWSFO issued a Severe Thunderstorm Warning for Sebastian

and Crawford Counties in Arkansas, including Ft. Smith and Van Buren. This warning

included a statement concerning the potential for tornadoes. A Tornado Warning was

issued for Sebastian and Crawford Counties at 11:08 p.m. 
xv

Finding 2.2

A significant factor which led to the initial issuance of a Severe Thunderstorm

Warning rather than a Tornado Warning was the perception that the tornadic

potential of the storm had begun to diminish. The Survey Team believes that the

warning team relied heavily throughout the evening on an assessment of the

strength of the mesocyclone using the radar’s Storm Relative Velocity Map (SRM)

product along with the Rotational Velocity (Vr) Shear function of the Principal

User Processor (PUP). This technique provided an assessment of the storm’s

tornadic potential as the storm moved from near McAlester, Oklahoma, to Stigler,

Oklahoma, allowing the tornado warnings issued by the Tulsa NWSFO for those

areas to provide 30 minutes lead time. However, slight changes in the storm

structure in the time just prior to the warning decision caused this technique to

provide ambiguous information which could be interpreted as a decrease in the

intensity of the mesocyclone. This interpretation contributed to the perception

that the tornadic potential of the storm had decreased. 

Recommendation 2.2a

The NWS should continue to provide training to increase the level of

understanding and appropriate use of new WSR-88D products and capabilities. 

Each successive software build for years to come will have new products and

additional functions. Continuous training using various distance learning

technologies appears to be an effective method for ensuring NWS field offices

have adequate knowledge of updated products and system functions.

Recommendation 2.2b

The WSR-88D provides forecasters with a wide variety of products that assess

the potential severity of storms. Forecasters diagnosing severe storms should

use the system to its fullest capability by examining a representative suite of

products in their evaluation.

Finding 2.3

A lack of damage reports immediately upstream of the Ft. Smith area may have

contributed to the warning decision to issue a Severe Thunderstorm Warning in

lieu of a Tornado Warning.

Recommendation 2.3

A lack of damage reports, especially at night or in sparsely populated areas,

should not play a significant role in the decision process regarding the issuance

of severe weather warnings, especially those involving tornadoes. Forecasters

should issue warnings based on the best available information derived from

various technologies and reports from trained spotters.
xvi

Finding 2.4

Another factor in the warning decision process was the appearance of

inconsistencies between locations of funnel clouds reported by spotters and the

mesocyclone location as depicted by the WSR-88D. This adversely affected the

use of spotter reports in the decision process.

Recommendation 2.4

Accurate, descriptive reports from trained spotters provide a valuable source of

ground truth which can enhance the interpretation of storm structure available

from radar or other remotely observed data. These reports can appear

geographically inconsistent with radar severe weather signatures for a number of

reasons, including the relative location of the weather observed to the spotter’s

position. When discrepancies exist, attempts should be made by office

personnel to resolve the discrepancies or obtain additional reports, if time

allows. No spotter report should be dismissed solely on the grounds of not

coinciding with the location of a radar signature. 

Finding 2.5

The severe weather statement issued at 11:02 p.m. concludes with “This is a

dangerous storm. If you live in the Ft. Smith or Van Buren areas, you should

move to a place of safety.”

Recommendation 2.5

Forecasters should tailor “Call to Action” statements in dangerous situations to

the specific conditions inherent in the storm, as this statement did.

D6. Fact

At 11:08 p.m. the Tulsa NWSFO issued a Tornado Warning for Sebastian and

Crawford Counties. This warning was based on the latest 0.5 degree Storm Relative

Velocity Map product from the Tulsa WSR-88D. Based on information provided by the

Oklahoma Gas & Electric Company on the time major power lines at the 3rd Street

substation broke, the Survey Team concluded that a tornado entered the Ft. Smith/Van

Buren area at the Garrison Street Bridge at 11:12 p.m.

Finding 2.6

During this event, personnel in the Ft. Smith Weather Service Office (WSO)

interacted routinely with local emergency management and law enforcement

officials in their former county warning area. They relayed critical warning

information generated by the Tulsa NWSFO, and collected and relayed spotter

information to the Tulsa office. Nevertheless, Ft. Smith personnel expressed

some confusion over the extent to which they are expected to be involved in the

warning process during severe weather events. 
xvii

Recommendation 2.6a

NWS should provide further clarification of the roles of personnel in spin-down

WSOs which maintain use of commissioned local warning radars.

Recommendation 2.6b

NWSFO Tulsa should enhance their working relationship with the Ft. Smith WSO

so that the WSO’s expertise on the local area, including the spotter network and

community contacts, can be integrated more fully into the warning process.

D7. Fact

The Tulsa NWSFO issued a Tornado Warning for the St. Paul area of Madison County

at 11:50 p.m., April 21, 1996 with a 25-minute lead time. A tornado subsequently

struck the community at approximately 12:15 a.m. on April 22, 1996.

E. Preparedness 

Finding 3.1 

Activities related to the transfer of county warning areas (CWA) from the Ft. Smith

WSO to the Tulsa NWSFO and Little Rock NWSFO began in 1990. The

Meteorologists-in-Charge (MICs) of Little Rock, Tulsa, and Ft. Smith participated

in many joint preparedness and awareness activities throughout the affected

area. In addition, the MIC and Warning Coordination Meteorologist (WCM) of

Tulsa have conducted numerous preparedness activities in the Ft. Smith area. 

The remaining staff of the Ft. Smith office also continue to remain involved in

hazard awareness activities. These activities have not always been well

coordinated between the Tulsa and Ft. Smith offices.

Recommendation 3.1

The NWS should accelerate the planned transfer of administrative responsibility

for the Ft. Smith WSO from NWSFO Little Rock to NWSFO Tulsa. This transfer

will facilitate the planning and coordination of joint preparedness and hazard

awareness activities.

E1. Fact

The Warning Coordination Meteorologist in Tulsa has been very effective in cultivating

positive media relationships in the Ft. Smith area. 

F. Communications and Dissemination

F1. Fact

The decision by several Ft. Smith radio and television stations to bring in extra

personnel to work throughout the storm was based on NWS reports and other

information available earlier in the evening. As a result, storm coverage was
xviii

expanded. Many area residents interviewed found this additional coverage to be

valuable.

F2. Fact

At least one television station uses an automated alert/warning display system that is

activated by the NWS’ universal generic code on warning products. This television

station reports this system is consistently faster in transmitting NWS warnings than is

the present NWR system.

Finding 4.1

Telephone calls and the National Warning System (NAWAS) were the primary

means the Tulsa NWSFO used to communicate warning information to local

officials in the Van Buren and Ft. Smith areas. Local officials did not have

access to severe weather information, including warnings, from any other mass

dissemination sources. As the Tulsa office initiated contact with Ft. Smith on the

NAWAS at 11:08 p.m. to convey the Tornado Warning, communication on the

NAWAS line was interrupted due to a power failure at the Ft. Smith police station. 

Attempts to phone both the Ft. Smith Police Department and Crawford County

officials on commercial lines were not successful. The sole remaining means of

providing warnings to Ft. Smith officials was through the Arkansas Law

Enforcement Telecommunications System (LETS). Warnings received on a

NOAA Weather Wire downlink in Little Rock were manually reentered onto this

statewide teletype system. Service from this system was also interrupted until

emergency power was restored. 

An additional factor affecting communications between Tulsa NWSFO and the Ft.

Smith Police Department was the change in operations of the NAWAS circuit due

to an operations upgrade which allowed a single phone to be used to contact

public officials across state lines. A review of the NAWAS archive tape suggests

an inconsistent level of understanding on NAWAS procedures by the Tulsa

NWSFO staff. In one instance, Tulsa NWSFO did not follow correct procedures

and, as a result, was unsuccessful in communicating information on a funnel

cloud report to the Ft. Smith Police.

Recommendation 4.1

The NWS should work with officials in Ft. Smith and surrounding areas to explore

methods to improve the communication of critical warning information in a timely

manner. Use of NWR, two-way radio, and Emergency Manager Weather

Information Network (EMWIN) should be a priority consideration. Cooperative

efforts between the NWS and Federal, State, and Local emergency management

agencies are essential for improving the flow of critical weather information into

the Ft. Smith and Van Buren areas.

Recommendation 4.2
xix

The NWS shall provide additional guidelines clarifying the operations of the

NAWAS regional circuits, and identifying protocols for calls within states and

across state lines. Local offices shall conduct training and perform drills to

ensure that these guidelines are followed during warning operations. 

F3. Fact

All warning products for the Ft. Smith area were broadcast by the Tulsa NWSFO using

the tone alert on the NWR transmitter serving Ft. Smith. These warnings were

broadcast live via NWR and taped during the initial live broadcast for subsequent

rebroadcast.

F4. Fact

Several media representatives monitor amateur radio reports during severe weather

events and value this input. 

G. User Response

G1. Fact

The low number of deaths and injuries, when compared to the area and intensity of

storm damage, suggests that most Ft. Smith and Van Buren residents knew what to do

and took appropriate protective action as the tornado approached. 

G2. Fact

Most health care facilities queried recognized the severe weather threat and

implemented their disaster action plans well in advance of the tornado’s arrival in Ft.

Smith. Specific actions taken included moving patients into hallways, and some noncritical personnel into emergency shelters. Four of the five facilities surveyed relied on

tone-alert NWR and monitored weather developments on television and radio as well.

Finding 5.1

A limited number of interviews conducted by the Disaster Survey Team revealed

no evidence of widespread NWR usage by residents of the disaster area.

Recommendation 5.1

The NWS should develop additional partnership initiatives with the public and

private sector to encourage the distribution and usage of NWR.
The parent tornadic storm continued moving northeast and produced another tornado shortly after 1 

midnight near the community of St. Paul, Arkansas, approximately 40 miles northeast of Van Buren. This

tornado resulted in two fatalities. A father and his 10 year old son were killed when the tornado struck and

destroyed their mobile home.

1

CHAPTER 1

DESCRIPTION AND IMPACT OF EVENT

During the afternoon and evening of April 21, 1996, and the early morning hours of

April 22, 1996, a major outbreak of tornadoes, severe thunderstorms, and flash flood

producing rainstorms occurred over much of southern and eastern Oklahoma and

northwest Arkansas. This severe weather episode resulted in four fatalities, dozens of

injuries and property damage estimated to be in excess of $500 million. The loss of

life, and much of the property damage which occurred was the result of nine tornadoes

which took place during course of the event, the most notable of which was the Fort

Smith/Van Buren, Arkansas, tornado.

The parent thunderstorm which produced the Fort Smith/Van Buren tornado had a long 

history. The storm developed during the late afternoon hours in south central

Oklahoma in the vicinity of Ardmore. The storm moved east northeast, producing three

significant tornadoes during its life history. The first struck McAlester, Oklahoma,

around 8 P.M., causing considerable property damage. The second significant tornado

was the Fort Smith/Van Buren tornado which occurred around 11:12 P.M. The third

tornado occurred shortly after midnight in the vicinity of St. Paul, Arkansas. This report

focuses on the Fort Smith/Van Buren tornado. 

The Fort Smith/Van Buren tornado first touched down at 11:12 p.m. on the Oklahoma

side of the Oklahoma/Arkansas state line near the confluence of the Arkansas and

Poteau Rivers in extreme southeast Sequoyah County. The tornado then moved into

the downtown Fort Smith business district near the Garrison Street bridge, doing

extensive damage to a number of historic buildings in the downtown area of the city. 

The tornado exited the business district, moved northeast into an industrial area, and

then into a residential section on the north side of Fort Smith. From there, it crossed

the Arkansas River once again and, at approximately 11:18 p.m., moved into a

residential area on the west side of Van Buren, Arkansas, destroying or heavily

damaging a number of homes. The tornado continued moving to the northeast for

approximately seven miles before dissipating in a rural area east of U.S. Highway 59 . 2

The total path length of the tornado was nearly 10 miles. As it moved through Fort

Smith proper, and the western section of Van Buren, the path width averaged

approximately one half mile. After crossing Highway 59 on the northwest side of Van

Buren, the path width gradually tapered to zero as the tornado dissipated.
2

Figure 1. General track of Ft. Smith/Van Buren Tornado showing location of two

fatalities (solid circles)

After the tornado first developed just to the west of the Arkansas River near the

Garrison Street Bridge, it rapidly spun-up to F2 intensity on the Fujita Scale (Appendix

A) and moved through the historic district in downtown Fort Smith. It continued

intensifying to F3 intensity as it entered the industrial and residential areas in northwest

and north Fort Smith. The tornado maintained F3 intensity as it moved through the

residential areas on the west side of Van Buren before beginning to weaken after

crossing Highway 59 (Fig. 1). 

Two fatalities occurred as the tornado moved through the residential area on the north

side of Fort Smith. A two year old girl was killed at 1917 High St., when a home 

collapsed. Several blocks away, a five year old boy was killed at 3419 N. 23rd. St. 

According to news reports, the boy was caught beneath the debris of the house as it

shifted from its foundation and subsequently collapsed. It is believed these deaths

occurred around 11:15 p.m.

Shortly after the tornado formed, it destroyed a high voltage transmission line which

crossed the Arkansas River and supplied a power substation on the west side of the

downtown area of Fort Smith. This resulted in an immediate, and widespread power

outage in much of west and north Fort Smith. Also heavily damaged were a number of

industrial buildings and warehouses on the east side of the river just to the north of the

downtown area. A number of railroad cars on tracks serving the industrial area were
3

Historic Downtown Ft. Smith Rogers Avenue, Downtown Ft.Smith

Vista Ridge subdivision, looking northeast

along track, Van Buren

F3 Damage, Vista Ridge subdivision, Van

Buren

Damaged home, Vista Ridge subdivision, Van

Buren

Damage to Industrial Buildings, Clayton

Parkway, Ft. Smith
4

 blown completely off the tracks. A newly completed wastewater treatment plant in this

same area sustained severe damage and was put out of commission. This resulted in

an undetermined amount of raw sewage being released into the Arkansas River.

In addition to damaging or destroying a number of residences on the north side of Fort

Smith, the tornado caused extensive damage to the Morrison Elementary School. 

Fortunately, since the storm occurred at night, the school was unoccupied. A number

of other schools in Fort Smith, including the Howard, Parker, and Trusty Elementary

Schools, the Kimmons Junior High School and the Northside High School also suffered

damage, but to a lesser extent.

In both Fort Smith and Van Buren, the electrical system and the phone system

infrastructure along and near the path of the tornado were extensively damaged.

In Van Buren, in addition to damaging or destroying a number of homes in the Vista

Ridge subdivision, the tornado damaged the Coleman Junior High School and severely

damaged a newly completed fire station including the fire engines inside. As the storm

crossed Interstate Highway 40, just a short distance south of the fire station, a number

of 18 wheel tractor trailer trucks were overturned. The drivers of the trucks had pulled

over and stopped because of reduced visibility in heavy rain which preceded the

tornado.

On Tuesday, April 23, 1996, President Clinton declared both Sebastian and Crawford

counties to be natural disaster areas. The Federal Emergency Management Agency

(FEMA) estimated that approximately 1800 homes in the two counties were either

severely damaged or destroyed along with 88 uninsured businesses in Sebastian

County and 10 uninsured businesses in Crawford County. Immediately after the

tornado struck, approximately 100 firefighters and 40 volunteers responded to help

search for victims. As late as Wednesday, April 24, about 130 electric company

workers were still working to restore power to almost 1500 homes and businesses. 

Because of the extensive damage, officials with the Oklahoma Gas and Electric

Company estimated that workers would be making repairs to the electrical system

infrastructure for weeks.
5

Figure 2 4/21/96 12Z Surface Weather Map

CHAPTER 2

METEOROLOGICAL ANALYSIS

Many of the meteorological parameters typically required for development of severe

thunderstorms were present over Oklahoma and northwest Arkansas the afternoon and

evening of April 21, 1996.

1200 UTC (6 a.m. CST) April 21, 1996 Features

The stage appeared set early in

the morning for a round of

severe thunderstorms from

Texas across Oklahoma into

eastern Kansas and western

Missouri that afternoon and

evening. The surface chart

(Fig. 2) featured a warm front

from New England across

Kentucky, Arkansas, and north

Texas to a developing low

pressure center in southeast

New Mexico. An area of low

pressure also reached from the

New Mexico Low northeast to

Minnesota. A warm, moist air

mass originating over the Gulf

of Mexico was poised to surge

northward. 

A progressive upper

atmospheric pattern was in place at 1200 UTC. A 300 millibar (mb) southwesterly jet

stream maximum (Fig. 3) of 100 knots (kts) reached from northern Baja California

across New Mexico. A broad 500 mb trough (Figure 4) was drifting east, and

embedded short waves were riding strong southwest flow toward north Texas and

Oklahoma. A more pronounced short wave was crossing Arizona. A low was taking

shape at the 850 mb level (Fig. 5) over west Texas with a low level jet of 35 kts from

east Texas into eastern Oklahoma.

The progressive nature of the pattern suggested the upper jet stream and 500 mb short

wave would shift east, increasing vertical wind shear in diffluent flow on the south side

of the upper jet. Increasing low level flow and accompanying moisture were also

expected. Studies have shown severe thunderstorms and tornadoes frequently form in

an area where strong upper level flow exists above strong low level flow with a sharp
6

Figure 3. 4/21/96 12Z 300mb

Heights/Winds (NGM)

Figure 5. 4/21/96 12Z 850mb Heights/

Winds (NGM)

Figure 4. 4/21/96 12Z 500mb Heights/

Vorticity (NGM)

difference (shear) in both direction and speed between the two. The SPC identified an

area, including eastern Oklahoma and far western Arkansas, as having a moderate risk

of severe thunderstorms that afternoon and night.

The 1200 UTC radiosonde launched from the Norman, OK, NWSFO showed a nearly

isothermal layer from the surface to about 800 mb that would likely inhibit convection

for a time. Above 800 mb, though, the atmosphere was quite unstable and a surface

temperature of about 75 degrees Fahrenheit would be enough to overcome the stable

low layer.
7

Figure 6. 4/21/96 18Z Sounding and Hodograph for Norman, OK,

NWSFO

1800 UTC Radiosonde Features

A special upper air sounding was taken at noon CST at the Norman, OK NWSFO

(Figure 6) to identify and quantify expected changes in the vertical atmospheric

structure. Data from that sounding confirmed rapid destabilization to a point that

severe weather was a near certainty, and tornadoes were likely. Indices traditionally

used to measure instability (and generally accepted thresholds for severe storms and

tornadoes) included: Lifted Index (LI) of minus 10 (less than minus 5), Total Total

Index of 62 (greater than 56), Severe Weather Threat (SWEAT) Index of 636 (greater

than 600), Energy Helicity Index (EHI) of 3.87 (greater than 2.0). Convective Available

Potential Energy (CAPE) was measured at 3708 J/kg with 3000 the threshold for strong

motion of 250 degrees at 23 kts was 154 m /s , which was slightly above the threshold 2 2
8

Figure 7. 4/22/96 00Z 300mb Heights/

Winds (NGM)

Figure 8. 4/22/96 00Z 500 mb

Heights/ Vorticity (NGM)

Figure 9. 4/22/96 00Z 850 mb Heights/

Winds (NGM)

of 150 for weak tornadoes. The data also showed an intrusion of extremely dry air

between 850 mb and 500 mb, which has also been shown to increase severe weather

potential.

0000 UTC, April 22, 1996 Features

Synoptic scale features at 0000 UTC, as expected, continued to support long-lived

supercell thunderstorms and a strong potential for tornadoes. Shear and instability

both continued quite strong. Severe thunderstorms were in progress across parts of

Oklahoma. The supercell that ultimately spawned the tornado that hit Fort Smith had

already developed over south central Oklahoma.

The 300 mb jet of 90 kts (Fig. 7) had

advanced northeast to a location from

eastern New Mexico to Iowa with eastern

Oklahoma and western Arkansas in a favored

area for severe storms, in diffluent flow near

the right rear section of the jet. The 500 mb

(Fig. 8) southwest flow continued strong with

a 70 kt maximum across Oklahoma and

eastern Kansas, and a series of embedded

impulses were in the flow headed toward

Oklahoma. An 850 mb (Fig. 9) jet of 40 kts

had an axis from east Texas into eastern

Oklahoma. 
9

 Figure 10. 4/22/96 00Z Sounding and Hodograph for 

 Norman, OK, NWSFO

The 0000 UTC upper air sounding taken at the Norman NWSFO (Fig.10) was

unfortunately launched with thunderstorms nearby. Temperature and moisture data

were not representative, but wind data and the hodograph appeared appropriate. 

Storm Relative Helicity (SRH) of 494 m /s was extremely high, indicating a strong 2 2

potential for low level shear induced rotation that could result in strong tornadoes. The

Springfield, MO 0000 UTC sounding (Fig. 11) showed an LI of minus 7, Total Total

Index of 59, SWEAT of 577, and CAPE of 1988. CAPE values, as initialized by the

ETA model, (Fig. 12) were maximized at 2000 J/kg across east Texas and LI (Fig. 13)

showed a minimum of minus 7 over the Fort Smith area.
10

 Figure 11. 4/22/96 00Z Sounding and Hodograph for 

 Springfield, MO, NWSO
11

Figure 12. 4/22/96 00Z CAPE values (ETA) Figure 13. 4/22/96 00Z Lifted Index (ETA)

Figure 14. 4/22/96 00Z Surface Analysis (SPC)

Mesoscale Analysis at 0000 and 0300 UTC

The subjectively analyzed 0000 UTC surface chart (Fig. 14) featured low pressure over

the Texas panhandle. The remains of the early morning warm front stretched from the

low across central Oklahoma into south central Kansas then east through Missouri into

the Ohio Valley. A fast moving cold front was advancing across central Kansas which

served to prolong the severe weather episode. Eastern Oklahoma and western

Arkansas remained in a strong southerly gradient with dew points around 60 and

temperatures between 75 and 80.
12

Figure 15. 4/22/96 03Z Surface Analysis (SPC)

At 0300 UTC the subjectively analyzed surface chart (Fig. 15) showed the cold front

had overtaken the west end of the warm front and had advanced into eastern Kansas,

central Oklahoma and west Texas. The southerly gradient had become even stronger

east of the front and a low pressure trough had developed from southeast Oklahoma

across central Arkansas. The trough had turned surface winds more easterly across

Arkansas increasing low level shear and helicity. 

The advancing front and shift of low level winds toward the east teamed with strong

synoptic features to continue the threat of tornadoes well into the night.

Summary

Nearly all synoptic and mesoscale indicators supported the initial development and

persistence of severe thunderstorms across Oklahoma and western Arkansas. 

Measures of instability and vertical wind shear both supported the potential for

tornadoes. The cold front advancing from the northwest served to enhance and

prolong the severe weather episode.
13

CHAPTER 3

OBSERVATIONAL EVALUATION

The Tulsa WSR-88D detected this supercell thunderstorm throughout its life cycle,

most of which was in the Tulsa County Warning Area (CWA). The base velocity and

storm relative velocity products indicated a strong mesocyclone almost continuously

from McAlester, Oklahoma, through Ft. Smith/Van Buren, Arkansas, and northeast into

the St. Paul area. Both the Tulsa WSR-88D radar, located 89 miles northwest of Ft.

Smith, and the Little Rock WSR-88D radar, located 126 miles east, showed a well

defined velocity couplet identifying the area of mesocyclone rotation as the storm

moved across the Ft. Smith area.

Figure 16 shows the base velocity from 10:49 pm to 11:06 pm, focusing on the area

identified within the blue box. At 10:49, the velocity couplet located northwest of Spiro,

OK, had a gate-to-gate velocity shear of at least 80 kts. By 10:54 pm the couplet was

northeast of Spiro. The couplet progressed half way between Spiro and Ft. Smith by

11:00 pm, and was just west of Ft. Smith at 11:06 pm, maintaining an 80 kt gate-to-gate

shear.

The radial shear was less striking on the Storm Relative Velocity Products (Fig. 17)

during this period. This is due in part to the 50 kt maximum velocity displayed with this

product, compared to 64 kt maximum on the base velocity. At 10:49 pm, the gate-togate shear of the couplet was at least 60 kts. This went to 55 kts at 10:54 pm and 60

kts at 11:00 pm. At 11:06 pm, the storm relative velocity product showed the same 80

kt gate-to-gate shear as the base velocity.

Base reflectivity products provided basic storm structure information. Figure 18 shows

a sequence of these products corresponding to the velocity products examined. The

gold circles on the series of figures are the mesocyclones identified by the WSR-88D

algorithms using base velocity data at all elevations. The thunderstorm which would

spawn the Ft. Smith/Van Buren tornado had a maximum reflectivity of between 55 and

62 dbz, had a mesocyclone 15,000 ft deep, and showed a strong inflow notch from

10:49 pm to 11:06 pm. At 11:18 pm, the WSR-88D Tornadic Vortex Signature (TVS)

algorithm detected a TVS near Van Buren. This is shown on the last reflectivity product

in Figure 18. 

Finding 1.1

The one-minute and five-minute Ft. Smith Automated Surface Observing System

(ASOS) data, which were not available in real-time, would have provided detailed

surface observation data for the Ft. Smith area. When integrated with the WSR88D data, additional information concerning the increased inflow into the

mesocyclone, as well as strong pressure falls as the storm approached, would

have been available to the forecasters in Tulsa.
14

Figure 16. Tulsa WSR-88D Base Velocity Products
4/22/96 04:00Z Tulsa WSR-88D

Storm Relative Velocity

4/22/96 04:06Z Tulsa WSR-88D

Storm Relative Velocity

Note increased velocity shear

15

Figure 17. Tulsa WSR-88D Storm Relative Velocity Products
4/22/96 04:18Z Tulsa WSR-88D 

Reflectivity.

Note Tornadic Vortex Signature (TVS) 

in Van Buren area

16

Figure 18. Tulsa WSR-88D Reflectivity Products
0

10

20

30

40

Time (5-minute Intervals)

Wind Speed (kts)

Wind Speed

Wind Gusts

Ft. Smith 5-Minute ASOS Data

4/21/96 10:00 pm - 4/22/96 12:15 am

0

90

180

270

360

Time (5-minute Intervals)

Wind Direction

Direction 

1003

1004

1005

1006

1007

1008

1009

Time (5-Minute Intervals)

Pressure (mb)

 Pressure 

17

Figure 19. 5-minute ASOS data showing fall in pressure and changes in

wind speed and direction at Ft. Smith airport (south and east of tornado

track)

Recommendation 1.1

The ability to access and display detailed ASOS data (Fig. 19) integrated with

radar and other data sources needs to be incorporated in the Advanced Weather

Information Processing System (AWIPS).
18

Figure 20. GOES 8 IR Image 4/22/96 04Z

In addition to the data from the WSR-88D radar, forecasters had access to infrared (IR)

and water vapor (WV) images from GOES 8 (Fig. 20). The Tulsa NWSFO also

received a continuous flow of reports from severe storm spotters via amateur radio. All

amateur radio and telephone reports received by the Ft. Smith office were called to the

Tulsa office in a timely manner.
19

CHAPTER 4

WARNINGS, FORECASTS, AND GUIDANCE

The storms which developed in southern Oklahoma and spawned the Ft. Smith/Van

Buren tornado on April 21, 1996, were not unexpected. The SPC in Kansas City,

Missouri, identified the potential for severe weather in the Oklahoma/Arkansas area

nearly two days prior to the onset of the outbreak. The SPC issued a Tornado Watch

which included the Ft. Smith and St. Paul areas three hours prior to the tornado striking

Ft. Smith and Van Buren. Effective from just after 8:00 pm CDT until 3:00 am on April

22, 1996, Tornado Watch Number 219 (Appendix C) said that “Tornados, large hail, 

dangerous lightning and damaging thunderstorm winds are possible in these areas.”

Finding 2.1

The Tulsa NEXRAD Weather Service Forecast Office (NWSFO) issued Public

Information Statements at 6 a.m. and 1 p.m. on April 21, 1996, regarding the

potential severe weather threat for the day, including the possibility of

tornadoes. These statements, while containing valuable information, were quite

lengthy, limiting their utility to the media.

Recommendation 2.1

Public Information Statements are designed to be used by the media to alert the

populace to a predicted weather event. Information contained in such statements

should be concise and easy to use. 

Tulsa NWSFO issued Public Information Statements at 6:00 am and 1:10 pm CDT April

21, 1996, which identified the threat of severe thunderstorms to eastern Oklahoma and

northwestern Arkansas. The 1:10 pm statement was just over 12 paragraphs long,

although only the first paragraph mentioned the expected weather by saying “An

outbreak of severe thunderstorms and tornadoes is expected across portions of eastern

Oklahoma and northwest Arkansas late this afternoon and tonight.” The balance of the

statement provided detailed information on the recommended actions to be taken for

the different severe weather threats.

The parent thunderstorm which spawned the Ft. Smith/Van Buren tornado produced its

first significant tornado earlier in the evening to the northeast of McAlester, OK. Tulsa

NWSFO issued a Severe Thunderstorm Warning (SVR) for McIntosh and Pittsburgh

Counties at 8:20 pm. This was upgraded to a Tornado Warning (TOR) at 8:57 pm

based on radar signatures associated with increasing tornadic potential and spotter

reports. A tornado was reported near McAlester, Oklahoma, in Pittsburgh County at

9:27 pm by McAlester, Oklahoma, Emergency Management. Tornado warnings were

extended at 9:30 pm to adjacent Haskell County and at 10:22 pm to north LaFlore and

south Sequoyah Counties in Oklahoma as the storm continued moving east northeast. 
20

During the period in which this dangerous storm system formed and moved, spawning a

series of tornadoes, Tulsa NWSFO was issuing frequent short term forecasts (NOW). 

The short term forecast is regularly available through commercial vendors, NWR, and

the NWWS. These are routinely displayed by the Weather Channel. A short term

forecast issued by the Tulsa NWSFO at 9:57 pm included Crawford and Sebastian

Counties in Arkansas, saying “A dangerous severe thunderstorm, capable of producing

a tornado, will move east northeast from the Quinton area of northeast Pittsburgh

County across the Kinta and Keota areas of Haskell County through 10:30 pm... These

storms will track across Sequoyah and far northern LeFlore County between 10:30 and

11 pm. If the storms hold together, they could threaten Ft. Smith, Arkansas, after 11

pm.” An additional NOW at 10:33 p.m. advised, “Dangerous severe thunderstorm

approaching the Ft. Smith area... If this storm holds together, it will affect the Ft. Smith,

Arkansas, area after 11 pm. In addition to tornadoes, this storm is capable of producing

hail up to golf ball size and winds up to 70 mph.” 

At 10:54 pm, the Tulsa NWSFO issued a Severe Thunderstorm Warning for southern

Crawford County and northern Sebastian County which identified the potential for

tornadoes. The warning specified “Hail to the size of quarters and gusts to 70 mph can

be expected in the warned area. A Tornado Watch is also in effect for the warned area. 

Remember, severe thunderstorms can and occasionally do produce tornadoes with

little or no advance warning.” At issue is why a Severe Thunderstorm Warning was

issued for a storm that had a known tornadic history. The NWS Disaster Survey Team

found that the Tulsa warning team perceived that the storm, while still dangerous, was

decreasing in tornadic potential and, therefore, issued a Severe Thunderstorm

Warning. 

Finding 2.2

A significant factor which led to the initial issuance of a Severe Thunderstorm

Warning rather than a Tornado Warning was the perception that the tornadic

potential of the storm had begun to diminish. The Survey Team believes that the

warning team relied heavily throughout the evening on an assessment of the

strength of the mesocyclone using the radar’s Storm Relative Velocity Map (SRM)

product along with the Rotational Velocity (Vr) Shear function of the Principal

User Processor (PUP). This technique provided an assessment of the storm’s

tornadic potential as the storm moved from near McAlester, Oklahoma, to Stigler,

Oklahoma, allowing the tornado warnings issued by the Tulsa NWSFO for those

areas to provide 30 minutes lead time. However, slight changes in the storm

structure in the time just prior to the warning decision caused this technique to

provide ambiguous information which could be interpreted as a decrease in the

intensity of the mesocyclone. This interpretation contributed to the perception

that the tornadic potential of the storm had decreased. 
21

Recommendation 2.2a

The NWS should continue to provide training to increase the level of

understanding and appropriate use of new WSR-88D products and capabilities. 

Each successive software build for years to come will have new products and

additional functions. Continuous training using various distance learning

technologies appears to be an effective method for ensuring NWS field offices

have adequate knowledge of updated products and system functions.

Recommendation 2.2b

The WSR-88D provides forecasters with a wide variety of products that assess

the potential severity of storms. Forecasters diagnosing severe storms should

use the system to its fullest capability by examining a representative suite of

products in their evaluation.

Finding 2.3

A lack of damage reports immediately upstream of the Ft. Smith area may have

contributed to the warning decision to issue a Severe Thunderstorm Warning in

lieu of a Tornado Warning.

Recommendation 2.3

A lack of damage reports, especially at night or in sparsely populated areas,

should not play a significant role in the decision process regarding the issuance

of severe weather warnings, especially those involving tornadoes. Forecasters

should issue warnings based on the best available information derived from

various technologies and reports from trained spotters.

Finding 2.4

Another factor in the warning decision process was the appearance of

inconsistencies between locations of funnel clouds reported by spotters and the

mesocyclone location as depicted by the WSR-88D. This adversely affected the

use of spotter reports in the decision process.

Recommendation 2.4

Accurate, descriptive reports from trained spotters provide a valuable source of

ground truth which can enhance the interpretation of storm structure available

from radar or other remotely observed data. These reports can appear

geographically inconsistent with radar severe weather signatures for a number of

reasons, including the relative location of the weather observed to the spotter’s

position. When discrepancies exist, attempts should be made by office

personnel to resolve the discrepancies or obtain additional reports, if time

allows. No spotter report should be dismissed solely on the grounds of not

coinciding with the location of a radar signature. 
22

Although the forecasters believed that the tornadic potential of the storm system was

decreasing, they did continue to monitor the storm closely. An SVS issued for

Sequoyah, LeFlore, Sebastian, and Crawford counties at 11:01 pm was strongly

worded and very concise. 

Finding 2.5

The severe weather statement issued at 11:01 p.m. concludes with “This is a

dangerous storm. If you live in the Ft. Smith or Van Buren areas, you should

move to a place of safety.”

Recommendation 2.5

Forecasters should tailor “Call to Action” statements in dangerous situations to

the specific conditions inherent in the storm, as this statement did.

At 11:08 pm the Tulsa NWSFO issued a Tornado Warning for Sebastian and Crawford

Counties. This warning was based on the latest 0.5 degree Storm Relative Velocity

Map product from the Tulsa WSR-88D. This indicated a marked increase in the

tornadic potential of the storm system. The warning indicated “At 11:08 pm radar

indicated a developing tornado near Ft. Smith. The tornado is moving northeast at 25

mph toward Van Buren. This is a dangerous situation. Act quickly...” This warning

was immediately relayed by the amateur radio operators to the spotter network and

media outlets which monitor the spotter reports. It was placed on NWR and NWWS. 

In addition, the Tulsa Warning Coordination Meteorologist (WCM) phoned the Ft. Smith

Police Department using the NAWAS connection to advise them of the warning. While

this call was underway, a power loss at the Ft. Smith Police Department caused a

failure of this primary communications method with Ft. Smith officials as well as the

failure of the Arkansas LETS, their secondary source for NWS warnings. This

deprived Ft. Smith officials of critical input to their decision to sound the Civil Defense

sirens. As a result, the sirens were not sounded. 

An additional short term forecast issued at 11:10 pm reinforced the tornado warning,

saying, “Severe thunderstorm with a possible tornado moving into the Ft. Smith and

Van Buren areas. A severe thunderstorm with hail up to golfball size and a possible

tornado will move across the Ft. Smith and Van Buren areas through 11:20 pm. 

Persons in the path of this dangerous storm should take cover immediately. The storm

will continue east northeastward over southern Crawford county through 11:45 pm.”

Based on information provided by the Oklahoma Gas & Electric Company on the time

major power lines at the 3rd Street substation broke, the Survey Team concluded that a

tornado entered the Ft. Smith/Van Buren area at the Garrison Street Bridge at 11:12

p.m. Interviews with the Ft. Smith Police Department revealed that reports were being

received about the tornado before the tornado warning finally came across the LETS
23

Figure 21. Location of tornadoes and spotter reports

printer. Spotter reports began almost as soon as the tornado formed. At 11:13 pm, a

severe weather statement was issued that said, “At 11:12 pm a funnel cloud was

reported almost to the ground in Ft. Smith. Radar indicated that a tornado was

developing in Ft. Smith. The tornado was moving northeast at 25 mph and will move

toward Van Buren. If you are in or around Ft. Smith and Van Buren seek shelter now!”

The parent cell of the Ft. Smith/ Van Buren tornado continued to the northeast. At

11:50 pm Tulsa NWSFO issued a Tornado Warning for southern Madison County,

warning the St. Paul area nearly 25 minutes before the tornado struck that community. 

The warning pointed to the effects of the earlier tornado spawned by this storm in Ft.

Smith, saying, “This storm has done significant damage in the Ft. Smith and Van Buren

areas.”

The Tulsa NWSFO detected and tracked the supercell thunderstorm which produced

the Ft. Smith/Van Buren tornado using the WSR-88D radar. In addition, the severe
24

weather spotter network servicing the Ft. Smith area and immediately adjacent counties

in Oklahoma provided timely reports to NWSFO Tulsa via amateur radio (Fig. 21). 

Some confusion was engendered between the Ft. Smith-based and Tulsa-based

spotter networks when an inexperienced volunteer amateur radio operator assisting in

severe weather operations in the Tulsa office needed clarification on locations in the Ft.

Smith area, although this was not a factor in use of the spotter reports by the

forecasters on duty. 

The NWS employee on duty in the Ft. Smith WSO maintained regular contact with local

authorities in Sequoyah and LeFlore Counties in Oklahoma and in Sebastian and

Crawford Counties in Arkansas. He received spotter reports which were relayed to

Tulsa, and phoned emergency managers and law enforcement officials to advise them

of warnings which had been issued by the Tulsa NWSFO or which were imminent. 

While this local liaison role provided a valuable resource to the Tulsa NWSFO, the Ft.

Smith WSO was uncertain of the amount of interpretive information or opinions which

should be provided to the forecasters at Tulsa. This confusion prevented the Ft. Smith

WSO from providing additional subjective input into the forecast decision process. 

Because the operating relationship between Ft. Smith WSO and Little Rock NWSFO

was long-standing and more clearly defined, subjective information was passed to Little

Rock NWSFO which might have benefitted Tulsa NWSFO.

Finding 2.6

During this event, personnel in the Ft. Smith Weather Service Office (WSO)

interacted routinely with local emergency management and law enforcement

officials in their former county warning area. They relayed critical warning

information generated by the Tulsa NWSFO, and collected and relayed spotter

information to the Tulsa office. Nevertheless, Ft. Smith personnel expressed

some confusion over the extent to which they are expected to be involved in the

warning process during severe weather events. 

Recommendation 2.6a

NWS should provide further clarification of the roles of personnel in spin-down

WSOs which maintain use of commissioned local warning radars.

Recommendation 2.6b

NWSFO Tulsa should enhance their working relationship with the Ft. Smith WSO

so that the WSO’s expertise on the local area, including the spotter network and

community contacts, can be integrated more fully into the warning process.
25

CHAPTER 5

PREPAREDNESS

Finding 3.1 

Activities related to the transfer of county warning areas (CWA) from the Ft. Smith

WSO to the Tulsa NWSFO and Little Rock NWSFO began in 1990. The

Meteorologists-in-Charge (MICs) of Little Rock, Tulsa, and Ft. Smith participated

in many joint preparedness and awareness activities throughout the affected

area. In addition, the MIC and Warning Coordination Meteorologist (WCM) of

Tulsa have conducted numerous preparedness activities in the Ft. Smith area. 

The remaining staff of the Ft. Smith office also continue to remain involved in

hazard awareness activities. These activities have not always been well

coordinated between the Tulsa and Ft. Smith offices.

Recommendation 3.1

The NWS should accelerate the planned transfer of administrative responsibility

for the Ft. Smith WSO from NWSFO Little Rock to NWSFO Tulsa. This transfer

will facilitate the planning and coordination of joint preparedness and hazard

awareness activities.

During the period April 1993 through April 1996, the NWSFO at Tulsa was active in the

Fort Smith area conducting MAR briefings and weather related preparedness

presentations and coordination. The MAR briefings provided information on the new

technology being implemented in the NWS, and in the plans for transitioning service

responsibility for the Fort Smith area from the WSO at Fort Smith to the NWSFO at

Tulsa. During the three year period, staff from NWSFO Tulsa met five times with either

representatives from the local Congressman and or representatives from the two U.S.

Senators from Arkansas, and twice with county and local officials. In addition, they met

with reporters from the Fort Smith newspaper twice; local HAM radio club three times;

and various general public groups five times. They provided interviews on Fort Smith

television stations eight times, and gave interviews on local Fort Smith radio stations

three times.

Tulsa NWSFO also conducted a number of weather preparedness related meetings

and briefings in the Fort Smith area during the same three year time period. They met

with county and local officials in Fort Smith on sixteen occasions; provided spotter

training to the local HAM radio club on seven occasions; provided preparedness

interviews to the Fort Smith newspaper on two occasions; conducted preparedness

presentations on local television stations seven times, and delivered awareness

presentations on Fort Smith radio stations two times. Severe weather information and

safety rules were provided to the general public during four presentations.
26

The efficacy of these preparedness presentations became readily apparent as the

Disaster Survey Team interviewed a number of people who were in the area of tornadic

destruction. Time and again, residents reported taking precisely those actions

recommended in severe weather preparedness materials and presentations, e.g., going

to an interior closet or hallway, or crouching in a bathtub and pulling padded material

(such as a mattress) on top for added protection from falling or flying debris. Although

any loss of life in such events is tragic, the extraordinarily low loss of life which

accompanied this strong tornado, which moved directly through a densely populated

area gives testament to the effectiveness of the preparedness activities which had

been undertaken in the Fort Smith area. 
27

CHAPTER 6

COMMUNICATIONS AND DISSEMINATION

Interviews were conducted with the lead weather anchor and the weather director of the

two local television stations, as well as one of the leading radio hosts, and the owner of

a local consulting firm. Both television stations, KPOM and KHBS, have access to

standard NWS products through NWWS or NWR. Both also supplement their

information with data from commercial services such as the First Warn System from

Acuweather. At least one television station uses an automated alert/warning display

system that is activated by the NWS’ universal generic code on warning products. This

television station reports this system is consistently faster in transmitting NWS

warnings than is the present NWR system. Both had key staff on duty because of the

severe weather, and both issued frequent updates during the evening news. 

The President and General Manager of a local radio station, KISR, monitors NWR,

receives rebroadcast NWWS products, watches broadcast and cable television

weather coverage, and monitors the local amateur radio network. Of these sources, he

feels the amateur spotter network provides the most timely reports. 

The owner of Video Base, a private consulting and video production firm, monitored the

evolving weather situation using television coverage, NWR, personal contacts in

Oklahoma, and the amateur spotter network. He felt that the NOWCASTS, if read on

NWR, would be disregarded because they were not identified as forecasts.

Finding 4.1

Telephone calls and the National Warning System (NAWAS) were the primary

means the Tulsa NWSFO used to communicate warning information to local

officials in the Van Buren and Ft. Smith areas. Local officials did not have

access to severe weather information, including warnings, from any other mass

dissemination sources. As the Tulsa office initiated contact with Ft. Smith on the

NAWAS at 11:08 p.m. to convey the Tornado Warning, communication on the

NAWAS line was interrupted due to a power failure at the Ft. Smith police station. 

Attempts to phone both the Ft. Smith Police Department and Crawford County

officials on commercial lines were not successful. The sole remaining means of

providing warnings to Ft. Smith officials was through the Arkansas Law

Enforcement Telecommunications System (LETS). Warnings received on a

NOAA Weather Wire downlink in Little Rock were manually reentered onto this

statewide teletype system. Service from this system was also interrupted until

emergency power was restored. 

An additional factor affecting communications between Tulsa NWSFO and the Ft.

Smith Police Department was the change in operations of the NAWAS circuit due

to an operations upgrade which allowed a single phone to be used to contact
28

public officials across state lines. A review of the NAWAS archive tape suggests

an inconsistent level of understanding of NAWAS procedures by the Tulsa

NWSFO staff. In one instance, Tulsa NWSFO did not follow proper procedures

and, as a result, was unsuccessful in communicating information on a funnel

cloud report to the Ft. Smith Police.

Recommendation 4.1

The NWS should work with officials in Ft. Smith and surrounding areas to explore

methods to improve the communication of critical warning information in a timely

manner. Use of NOAA Weather Radio (NWR), two-way radio, and Emergency

Manager Weather Information Network (EMWIN) should be a priority

consideration. Cooperative efforts between the NWS and Federal, State, and

Local emergency management agencies are essential for improving the flow of

critical weather information into the Ft. Smith and Van Buren areas.

Recommendation 4.2

The NWS shall provide additional guidelines clarifying the operations of the

NAWAS regional circuits, and identifying protocols for calls within states and

across state lines. Local offices shall conduct training and perform drills to

ensure that these guidelines are followed during warning operations.

All warning products for the Ft. Smith area were broadcast by the Tulsa NWSFO using

the tone alert on the NWR transmitter serving Ft. Smith. These warnings were

broadcast live via NWR and taped during the initial live broadcast for subsequent

rebroadcast. 
29

CHAPTER 7

USER RESPONSE

Interviews conducted by the Team with survivors in some of the severely damaged

areas of Ft. Smith and Van Buren identified no one who owned a NOAA Weather Radio

(NWR). Most were not monitoring their televisions or radios, although they were

usually aware of expected thunderstorm activity from reports earlier in the day. Many

of the residents interviewed were awakened by the hail and high winds which preceded

the tornado and responded by moving to interior hallways or bathrooms. The low

number of deaths and injuries, when compared to the area and intensity of storm

damage, suggests that most Ft. Smith and Van Buren residents knew what to do and

took appropriate protective action as the tornado approached. 

Finding 5.1

A limited number of interviews conducted by the Disaster Survey Team revealed

no evidence of widespread NWR usage by residents of the disaster area.

Recommendation 5.1

The NWS should develop additional partnership initiatives with the public and

private sector to encourage the distribution and usage of NWR.

To determine the impact of the NWS warning process on local area hospitals and

nursing homes, interviews were conducted with a nursing supervisor at one area

hospital and the directors of four area nursing homes. At St. Edwards Hospital, a

“Code Green” was declared when the Tornado Watch was issued. This increases the

staff’s readiness stance and requires increased monitoring of the television and NWR. 

A “Code Black” was declared at 11:04 pm as a result of the severe thunderstorm

warning and mention of tornadoes in the area. At this stage, ambulatory patients are

moved into the corridors and bed-ridden patients are covered. Non-essential

personnel are evacuated to the basement. After the tornado struck, the hospital moved

into “Code Delta” status, calling doctors to report to the hospital.

Directors at three of the four nursing homes had plans which relied on NWR and

television reports to monitor severe weather situations. Brownwood Manor had taken

their steps to protect patients at about 10:30. The Methodist Home was aware of the

storm history and earlier tornadoes. They monitored a NWR at each nursing station

and had moved patients into hallways well in advance of the tornado. The Rose Care

Center depends almost entirely on the NWR for weather information. They initiated

their disaster plan about 10:50, and had their patients in the hallways before the storm

hit. The final nursing center, Oaks Lodge, did not have a NWR, had no warning, and

had taken no action to prepare for the storm. They had, however, already purchased a

NWR prior to the interview.
A-1

APPENDIX A

FUJITA TORNADO INTENSITY SCALE

Category Definition and Effect

(F0) Gale tornado (40-72 mph): Light damage. Some damage to chimneys;

break branches off trees; push over shallow-rooted trees; damage sign

boards.

(F1) Moderate tornado (73-112 mph): Moderate damage. The lower limit is the

beginning of hurricane wind speed; peel surface off roofs; mobile homes

pushed off foundations or overturned; moving autos pushed of the roads.

(F2) Significant tornado (113-157 mph): Considerable damage. Roofs torn off

frame houses; mobile homes demolished; boxcars pushed over; large

trees snapped or uprooted; light-object missiles generated.

(F3) Severe tornado (158-206 mph): Severe damage. Roofs and some walls

torn off well-constructed houses; trains overturned; most trees in forest

uprooted; heavy cars lifted off ground and thrown.

(F4) Devastating tornado (207-260 mph): Devastating damage. Wellconstructed houses leveled; structure with weak foundation blown off

some distance; cars thrown and large missiles generated.

(F5) Incredible tornado (261-318 mph): Incredible damage. Strong frame

houses lifted off foundations and carried considerable distance to

disintegrate; automobile sized missiles fly through the air in excess of 100

yards; trees debarked; incredible phenomena will occur.
B-1

APPENDIX B

VERIFICATION STATISTICS FOR COMMON COUNTY WARNING AREAS

TULSA, OK, VERSUS FORT SMITH, AR

Periods of comparison and responsible offices

Baseline: Fort Smith WSO (FSM), AR 1986 - 1990

Transition: Fort Smith WSO, AR 1991 - July 6, 1994

Post-Transfer: Tulsa NWSFO (TUL), OK July 7, 1994 - 1995

Area of Concern:

Seven counties in FSM County Warning Area (CWA) transferred to TUL

Sebastian County, AR

Crawford County, AR

Benton County, AR

Washington County, AR

Madison County, AR

Sequoyah County, OK

LeFlore County, OK

All Severe Local Storms

POD FAR Ave. Lead Time (min) 12 3

Baseline 175/238 = .74 207/349 = .59 19.2 

Transition 240/284 = .85 252/616 = .41 18.1

Post-Transfer 186/218 = .85 51/216 = .24 16.5

Tornado Only

POD FAR Ave. Lead Time (min)

Baseline 1/6 = .17 14/15 = .93 1.2 

Transition 9/12 = .75 36/44 = .82 15.8

Post-Transfer 5/5 = 1.00 12/16 = .75 18.6

Probability of Detection (POD) is the percentage of actual events in any affected county for which a 1

warning was in effect so that POD equals warned events/total events. 1.0 is perfect.

False Alarm Ratio (FAR) is the percentage of warnings issued or extended for any county for which 2

no verifying event has been reported so that FAR equals missed county warnings/total county

warnings. 0.0 is perfect.

Lead Time is the elapsed time between the issuance of a county warning and the onset of the 3

event for which the warning was in effect. Average Lead Time (Ave Lead Time) equals the sum of

the lead time for each warning/number of verified warnings.
C-1

APPENDIX C

Watches, Warnings, and Statements

Summary (Watches and Warnings):

Tornado Watch 219 SPC 4/21/96 8:16pm

OKCSVRTUL- McIntosh, Pittsburg Co., OK TUL 4/21/96 8:20pm

OKCTORTUL- McIntosh, Pittsburg Co., OK TUL 4/21/96 8:57pm

OKCTORTUL- Haskell Co., OK TUL 4/21/96 9:30pm

OKCTORTUL- Pittsburg Co., OK TUL 4/21/96 9:39pm

OKCTORTUL- Haskell Co., OK TUL 4/21/96 10:05pm

OKCTOTTUL- Sequoyah, LeFlore Co., OK TUL 4/21/96 10:22pm

OKCSVRTUL- Crawford, Sebastian Co., AR TUL 4/21/96 10:54pm

OKCTORTUL- Crawford, Sebastian Co., AR TUL 4/21/96 11:08pm

OKCTORTUL- Crawford Co., AR TUL 4/21/96 11:26pm

OKCTORTUL- Madison Co., AR TUL 4/21/96 11:50pm

Summary (Advisories and Statements):

OKCSPSTUL- East OK and NW AR TUL 4/21/96 6:00am

Public Information Statement TUL 4/21/96 1:10pm

OKCSVSTUL- Haskell Co., OK TUL 4/21/96 9:53pm

OKCNOWTUL- East OK, NW AR TUL 4/21/96 9:57pm

OKCSVSTUL- Stigler, Keoto, OK TUL 4/21/96 10:14pm

OKCSVSTUL- Sequoyah, LeFlore, Haskell Co TUL 4/21/96 10:28pm

OKCNOWTUL- East OK, NW AR TUL 4/21/96 10:33pm

OKCSVSTUL- LeFlore, Haskell Co,., OK TUL 4/21/96 10:36pm

OKCSVSTUL- LeFlore Co., OK TUL 4/21/96 10:40pm

OKCSVSTUL- Sequoyah, LeFlore Co., OK TUL 4/21/96 10:49pm

OKCSVSTUL- East OK, NW AR TUL 4/21/96 11:01pm

OKCNOWTUL- Crawford, Sebastian Co., AR TUL 4/21/96 11:10pm

OKCSVSTUL- Ft. Smith, AR TUL 4/21/96 11:13pm

OKCSVSTUL- Crawford, Sebastian Co., AR TUL 4/21/96 11:22pm

OKCNOWTUL- Madison Co., AR TUL 4/22/96

12:08am
C-2

ZCZC MKCSAW9 ALL 220800;334,0971 374,0935 374,0912 334,0944;

WWUS40 KMKC 220111

^^MKC AWW 220111

WW 219 TORNADO OK AR MO 220200Z - 220800Z

AXIS..70 STATUTE MILES EAST AND WEST OF LINE..

30ESE DUA/DURANT OK/ - 50NE SGF/SPRINGFIELD MO/

..AVIATION COORDS.. 60NM E/E /64S MLC - 37NE SGF/

HAIL SURFACE AND ALOFT..3 INCHES. WIND GUSTS - 70 KNOTS.

MAX TOPS TO 600. MEAN WIND VECTOR 23035.

REPLACES WW 215.. OK AR MO

REPLACES WW 217.. OK

NNNN

ZCZC MKCSEL9 ALL 220800;334,0971 374,0935 374,0912 334,0944;

WWUS9 KMKC 220116

^^MKC WW 220116

OKZ000-ARZ000-MOZ000-220800-

BULLETIN - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 219

NATIONAL WEATHER SERVICE KANSAS CITY MO

816 PM CDT SUN APR 21 1996

.A..THE STORM PREDICTION CENTER HAS ISSUED A 

TORNADO WATCH FOR

PARTS OF EASTERN OKLAHOMA

PARTS OF WESTERN ARKANSAS

PARTS OF SOUTHWEST MISSOURI

EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING UNTIL 300 AM CDT.

TORNADOES...LARGE HAIL...DANGEROUS LIGHTNING AND DAMAGING

THUNDERSTORM WINDS ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 70 STATUTE MILES EAST AND

WEST OF A LINE FROM 30 MILES EAST SOUTHEAST OF DURANT OKLAHOMA TO

50 MILES NORTHEAST OF SPRINGFIELD MISSOURI.

REMEMBER... A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH

AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR

THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS

AND POSSIBLE WARNINGS.
C-3

B..OTHER WATCH INFORMATION.. THIS TORNADO WATCH REPLACES

TORNADO WATCH NUMBER 215. WATCH NUMBER 215 WILL NOT BE IN EFFECT

AFTER 900 PM CDT.

IN ADDITION.. THIS TORNADO WATCH REPLACES TORNADO WATCH NUMBER

217. WATCH NUMBER 217 WILL NOT BE IN EFFECT AFTER 900 PM CDT

$$

C...TORNADOES AND A FEW SVR TSTMS WITH HAIL SFC AND ALF TO 3 IN.

EXTRM TURBC AND SFC WND GUSTS TO 70 KNOTS. A FEW CBS WITH MAX

TOPS TO 600. MEAN WIND VECTOR 23035.

D...WITH LOW LVL JET INCRG AND STILL VERY MOIST/UNSTBL WARM

SECTOR SUPERCELLS/TORNADO THREAT WILL CONT.

E...OTR TSTMS... THIS WATCH REPLACES..WW215..WW217.. CONT...WW

213..WW 214..WW 216..WW 218..

...HALES

NNNN
C-4

ZCZC OKCSVRTUL

TTAA00 KTUL 220121

OKC091-121-220215-

BULLETIN - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WARNING

NATIONAL WEATHER SERVICE TULSA OK

820 PM CDT SUN APR 21 1996

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A SEVERE

THUNDERSTORM WARNING EFFECTIVE UNTIL 915 PM CDT

FOR THE PEOPLE IN THE FOLLOWING LOCATIONS...

IN EAST CENTRAL OKLAHOMA

...MCINTOSH COUNTY

IN SOUTHEAST OKLAHOMA

...PITTSBURG COUNTY

AT 816PM...RADAR SHOWED A SEVERE THUNDERSTORM CENTERED 15 MILES

SOUTHWEST OF HANNAH. IT WAS MOVING NORTHEAST AT 25 MPH AND WILL

TRACK ALONG THE MCINTOSH...PITTSBURG COUNTY LINE AND OVER THE

EUFAULA LAKE AREA. ANOTHER STRONG THUNDERSTORM MAY MOVE INTO

SOUTHERN PITTSBURG COUNTY...MOVING EAST OUT OF NORTHERN COAL

COUNTY.

HAIL TO THE SIZE OF QUARTERS AND WIND GUSTS TO 70 MPH CAN BE

EXPECTED IN THE WARNED AREA.

A TORNADO WATCH IS ALSO IN EFFECT FOR THE WARNED AREA. 

REMEMBER... SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO

PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE WARNING. REMAIN

CALM BUT BE ALERT TO RAPIDLY CHANGING WEATHER CONDITIONS.

KEEP TUNED TO THIS STATION FOR THE LATEST WEATHER BULLETINS.

NNNN
C-5

ZCZC OKCTORTUL

TTAA00 KTUL 220158

OKC091-121-220245-

BULLETIN - EBS ACTIVATION REQUESTED

TORNADO WARNING

NATIONAL WEATHER SERVICE TULSA OK

857 PM CDT SUN APR 21 1996

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

TORNADO WARNING EFFECTIVE UNTIL 945 PM CDT

FOR THE PEOPLE IN THE FOLLOWING LOCATIONS...

IN EAST CENTRAL OKLAHOMA

...SOUTHERN MCINTOSH COUNTY

IN SOUTHEAST OKLAHOMA

...NORTHERN PITTSBURG COUNTY

AT 856 PM SPOTTERS AND RADAR INDICATED A TORNADO ON THE INDIAN

NATION TURNPIKE...7 MILES WEST OF INDIANOLA. THE STORM IS MOVING

NORTHEAST AT 30 MPH...HANNA...INDIANOLA AND EUFAULA ARE IN THE PATH

OF THIS STORM.

THIS IS A DANGEROUS STORM SITUATION. ACT QUICKLY. IF YOU ARE IN THE

PATH OF THIS TORNADO MOVE TO A SHELTER BELOW GROUND IF AVAILABLE. 

OTHERWISE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR

POSSIBLE. STAY AWAY FROM OUTSIDE WALLS AND AVOID WINDOWS. 

ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING OR GET IN

A GROUND DEPRESSION.

KEEP TUNED TO THIS STATION FOR THE LATEST WEATHER BULLETINS.

NNNN
C-6

ZCZC OKCTORTUL

TTAA00 KTUL 220231

OKC061-220315-

BULLETIN - EBS ACTIVATION REQUESTED

TORNADO WARNING

NATIONAL WEATHER SERVICE TULSA OK

930 PM CDT SUN APR 21 1996

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

TORNADO WARNING EFFECTIVE UNTIL 1015 PM CDT

FOR THE PEOPLE IN THE FOLLOWING LOCATIONS...

IN SOUTHEAST OKLAHOMA

...HASKELL COUNTY

AT 929 PM RADAR INDICATED A TORNADO 13 MILES SOUTHWEST OF

ENTERPRISE OR NEAR BLOCKER IN PITTSBURG COUNTY. THIS STORM

PRODUCED A TORNADO IN MCALESTER. THE TORNADO IS MOVING EAST

NORTHEAST AT 25 MPH. IF YOUR IN BLOCKER...ENTERPRISE AND QUINTON

YOU SHOULD BE IN A PLACE OF SAFETY.

THIS IS A DANGEROUS STORM SITUATION. ACT QUICKLY. IF YOU ARE IN THE

PATH OF THIS TORNADO MOVE TO A SHELTER BELOW GROUND IF AVAILABLE. 

OTHERWISE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR

POSSIBLE. STAY AWAY FROM OUTSIDE WALLS AND AVOID WINDOWS. 

ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING OR GET IN

A GROUND DEPRESSION.

WATCH FOR SIGNS OF DEVELOPING STORMS. LARGE HAILSTONES AND

UNUSUALLY LOW SWIRLING CLOUDS ARE MANY TIMES SEEN NEAR

DEVELOPING TORNADOES. STRONG DAMAGING WINDS AND TORNADOES

OFTEN PRODUCE A LOUD ROARING SOUND THAT CAN BE HEARD IN THE

VICINITY OF STORMS. FREQUENT AND DANGEROUS LIGHTNING OCCURS

WITH MOST SEVERE THUNDERSTORMS.

KEEP TUNED TO THIS STATION FOR THE LATEST WEATHER BULLETINS.

NNNN
C-7

ZCZC OKCTORTUL

TTAA00 KTUL 220240

OKC121-220300-

BULLETIN - EBS ACTIVATION REQUESTED

TORNADO WARNING

NATIONAL WEATHER SERVICE TULSA OK

939 PM CDT SUN APR 21 1996

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

TORNADO WARNING EFFECTIVE UNTIL 1000 PM CDT

FOR THE PEOPLE IN THE FOLLOWING LOCATIONS...

IN SOUTHEAST OKLAHOMA

...NORTHERN PITTSBURG COUNTY

AT 939 PM RADAR INDICATED A POSSIBLE TORNADO JUST NORTHEAST OF

BLOCKER. QUINTON IS IN THE PATH OF THIS STORM.

THIS IS A DANGEROUS STORM SITUATION. ACT QUICKLY. IF YOU ARE IN THE

PATH OF THIS TORNADO MOVE TO A SHELTER BELOW GROUND IF AVAILABLE. 

OTHERWISE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR

POSSIBLE. STAY AWAY FROM OUTSIDE WALLS AND AVOID WINDOWS. 

ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING OR GET IN

A GROUND DEPRESSION.

KEEP TUNED TO THIS STATION FOR THE LATEST WEATHER BULLETINS.

NNNN
C-8

ZCZC OKCTORTUL

TTAA00 KTUL 220306

OKC061-220345-

BULLETIN - EBS ACTIVATION REQUESTED

TORNADO WARNING

NATIONAL WEATHER SERVICE TULSA OK

1005 PM CDT SUN APR 21 1996

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

TORNADO WARNING EFFECTIVE UNTIL 1000 PM CDT

FOR THE PEOPLE IN THE FOLLOWING LOCATIONS...

IN SOUTHEAST OKLAHOMA

...HASKELLCOUNTY

AT1003 PM RADAR INDICATED A TORNADO 5 MILES SOUTHWEST OF STIGLER. 

THE TORNADO WAS MOVING EAST NORTHEAST AT 25 MPH. STIGLER AND

KEOTA ARE IN THE PATH OF THE TORNADO. IF YOU ARE IN THESE AREAS

TAKE SHELTER NOW!

THIS IS A DANGEROUS STORM SITUATION. ACT QUICKLY. IF YOU ARE IN THE

PATH OF THIS TORNADO MOVE TO A SHELTER BELOW GROUND IF AVAILABLE. 

OTHERWISE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR

POSSIBLE. STAY AWAY FROM OUTSIDE WALLS AND AVOID WINDOWS. 

ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING OR GET IN

A GROUND DEPRESSION.

KEEP TUNED TO THIS STATION FOR THE LATEST WEATHER BULLETINS.

NNNN
C-9

ZCZC OKCTORTUL

TTAA00 KTUL 220323

OKC135-079-220415-

BULLETIN - EBS ACTIVATION REQUESTED

TORNADO WARNING

NATIONAL WEATHER SERVICE TULSA OK

1022 PM CDT SUN APR 21 1996

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

TORNADO WARNING EFFECTIVE UNTIL 1115 PM CDT

FOR THE PEOPLE IN THE FOLLOWING LOCATIONS...

IN EAST CENTRAL OKLAHOMA

...SOUTHERN SEQUOYAH COUNTY

IN SOUTHEAST OKLAHOMA

...NORTHERN LE FLORE COUNTY

AT1020 PM SPOTTERS REPORTED A TORNADO NEAR STIGLER. RADAR

SHOWED THIS STORM MOVING EAST NORTHEAST AT 25 MPH.

KINTA...BOKOSHE...COWLINGTON...GANS...AND MULDROW ARE IN THE PATH

OF THIS TORNADO.

THIS IS A DANGEROUS STORM SITUATION. ACT QUICKLY. IF YOU ARE IN THE

PATH OF THIS TORNADO MOVE TO A SHELTER BELOW GROUND IF AVAILABLE. 

OTHERWISE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR

POSSIBLE. STAY AWAY FROM OUTSIDE WALLS AND AVOID WINDOWS. 

ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING OR GET IN

A GROUND DEPRESSION.

KEEP TUNED TO THIS STATION FOR THE LATEST WEATHER BULLETINS.

&

NNNN
C-10

ZCZC OKCSVRTUL

TTAA00 KTUL 220356

ARC131-220445-

BULLETIN - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WARNING

NATIONAL WEATHER SERVICE TULSA OK

1054 PM CDT SUN APR 21 1996

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A SEVERE

THUNDERSTORM WARNING EFFECTIVE UNTIL 1145 PM CDT

FOR THE PEOPLE IN THE FOLLOWING LOCATIONS...

IN NORTHWEST ARKANSAS

...SOUTHERN CRAWFORD COUNTY

IN WEST CENTRAL ARKANSAS

...NORTHERN SEBASTIAN COUNTY

AT 1053 PM A DANGEROUS SEVERE THUNDERSTORM EXTENDED FROM

MULDROW TO SPIROW. THIS STORM WAS MOVING EAST NORTHEAST AT 35

MPH ASND WILL MOVE INTO FORT SMITH AND VAN BUREN.

HAIL TO THE SIZE OF QUARTERS AND WIND GUSTS TO 70 MPH CAN BE

EXPECTED IN THE WARNED AREA.

A TORNADO WATCH IS ALSO IN EFFECT FOR THE WARNED AREA. 

REMEMBER... SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO

PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE WARNING. REMAIN

CALM BUT BE ALERT TO RAPIDLY CHANGING WEATHER CONDITIONS.

NNNN
C-11

ZCZC OKCTORTUL

TTAA00 KTUL 220410

ARC033-131-220500-

BULLETIN - EBS ACTIVATION REQUESTED

TORNADO WARNING

NATIONAL WEATHER SERVICE TULSA OK

1108 PM CDT SUN APR 21 1996

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

TORNADO WARNING EFFECTIVE UNTIL MIDNIGHT CDT

FOR THE PEOPLE IN THE FOLLOWING LOCATIONS...

IN NORTHWEST ARKANSAS

...SOUTHERN CRAWFORD COUNTY

IN WEST CENTRAL ARKANSAS

...NORTHERN SEBASTIAN COUNTY

AT 1108 PM RADAR INDICATED A DEVELOPING TORNADO NEAR FORT SMITH. 

THE TORNADO IS MOVING NORTHEAST AT 25 MPH TOWARD VAN BUREN.

THIS IS A DANGEROUS STORM SITUATION. ACT QUICKLY. IF YOU ARE IN THE

PATH OF THIS TORNADO MOVE TO A SHELTER BELOW GROUND IF AVAILABLE. 

OTHERWISE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR

POSSIBLE. STAY AWAY FROM OUTSIDE WALLS AND AVOID WINDOWS. 

ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING OR GET IN

A GROUND DEPRESSION.

KEEP TUNED TO THIS STATION FOR THE LATEST WEATHER BULLETINS.

NNNN
C-12

ZCZC OKCTORTUL

TTAA00 KTUL 220427

ARC033-220515-

BULLETIN - EBS ACTIVATION REQUESTED

TORNADO WARNING

NATIONAL WEATHER SERVICE TULSA OK

1126 PM CDT SUN APR 21 1996

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

TORNADO WARNING EFFECTIVE UNTIL 1215 AM CDT

FOR THE PEOPLE IN THE FOLLOWING LOCATIONS...

IN NORTHWEST ARKANSAS

...CRAWFORD COUNTY

AT 1125 PM A TORNADO WAS REPORTED AND INDICATED BY DOPPLER RADAR

4 MILES NORTHEAST OF VAN BUREN. THE TORNADO WAS MOVING

NORTHEAST AT 30 MPH. DAMAGE WAS DONE IN VAN BUREN AND FORT SMITH.

IF YOU ARE NEAR MOUNTAINSBURG...ALMA...AND CHESTER SEEK SHELTER

NOW!

THIS IS A DANGEROUS STORM SITUATION. ACT QUICKLY. IF YOU ARE IN THE

PATH OF THIS TORNADO MOVE TO A SHELTER BELOW GROUND IF AVAILABLE. 

OTHERWISE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR

POSSIBLE. STAY AWAY FROM OUTSIDE WALLS AND AVOID WINDOWS. 

ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING OR GET IN

A GROUND DEPRESSION.

KEEP TUNED TO THIS STATION FOR THE LATEST WEATHER BULLETINS.

&

NNNN
C-13

ZCZC OKCTORTUL

TTAA00 KTUL 220452

ARC033-220515-

BULLETIN - EBS ACTIVATION REQUESTED

TORNADO WARNING

NATIONAL WEATHER SERVICE TULSA OK

1150 PM CDT SUN APR 21 1996

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

TORNADO WARNING EFFECTIVE UNTIL 1230 AM CDT

FOR THE PEOPLE IN THE FOLLOWING LOCATIONS...

IN NORTHWEST ARKANSAS

...SOUTHERN MADISON COUNTY

AT 1149 PM RADAR INDICATED A POSSIBLE TORNADO 15 MILES SOUTHWEST

OF ST. PAUL. THE TORNADO WAS MOVING NORTHEAST AT 35 MPH AND WILL

MOVE INTO THE COMBS AND ST. PAUL AREA. IF YOU ARE IN THESE AREAS

SEEK SHELTER IMMEDIATELY.

THIS STORM HAS DONE SIGNIFICANT DAMAGE IN THE FORT SMITH AND VAN

BUREN AREAS..

THIS IS A DANGEROUS STORM SITUATION. ACT QUICKLY. IF YOU ARE IN THE

PATH OF THIS TORNADO MOVE TO A SHELTER BELOW GROUND IF AVAILABLE. 

OTHERWISE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR

POSSIBLE. STAY AWAY FROM OUTSIDE WALLS AND AVOID WINDOWS. 

ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING OR GET IN

A GROUND DEPRESSION.

WATCH FOR SIGNS OF DEVELOPING STORMS. LARGE HAILSTONES AND

UNUSUALLY LOW SWIRLING CLOUDS ARE MANY TIMES SEEN NEAR

DEVELOPING TORNADOES. STRONG DAMAGING WINDS AND TORNADOES

OFTEN PRODUCE A LOUD ROARING SOUND THAT CAN BE HEARD IN THE

VICINITY OF STORMS. FREQUENT AND DANGEROUS LIGHTNING OCCURS

WITH MOST SEVERE THUNDERSTORMS.

NNNN
C-14
C-15
C-17

ZCZC OKCSPSTUL

TTAA KTUL 211100

ARZ001-002-010-011-019-029-OKZ054>077-221100-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS THUNDERSTORM OUTLOOK

NATIONAL WEATHER SERVICE TULSA OK

600 AM CDT SUN APR 21 1996

NUMEROUS SEVERE THUNDERSTORMS ARE EXPECTED OVER EASTERN OKLAHOMA

AND NORTHWEST ARKANSAS LATER TODAY THROUGH TONIGHT.

EARLY THIS MORNING A STATIONARY FRONTAL BOUNDARY WAS LOCATED ACROSS

TEXAS WITH A VERY MOIST AND UNSTABLE AIRMASS TO THE SOUTH OF THE

BOUNDARY. THE FRONT IS EXPECTED TO MOVE NORTHWARD AS A WARM FRONT

TODAY AS STRONG SOUTHERLY JET STREAM WINDS CONTINUE TO STRENGTHEN. 

THIS WILL SPREAD THE MOIST AND UNSTABLE AIR BACK INTO EASTERN OKLAHOMA

AND NORTHWEST ARKANSAS.

SCATTERED THUNDERSTORMS MAY DEVELOP NEAR THE RED RIVER DURING THE

MORNING WHICH WOULD THEN SPREAD NORTHWARD... HOWEVER THE MAIN THREAT

OF SEVERE THUNDERSTORMS WILL BE LATE THIS AFTERNOON INTO TONIGHT.

BY LATE THIS AFTERNOON A DEVELOPING LOW PRESSURE SYSTEM WILL BE LOCATED

JUST SOUTH OF THE RED RIVER IN NORTHWEST TEXAS. A DRYLINE WILL EXTEND

SOUTHWARD...AND THE WARM FRONT WILL STRETCH EASTWARD ACROSS EASTERN

OKLAHOMA AND NORTHWEST ARKANSAS. ANOTHER IN A SERIES O UPPER LEVEL

DISTURBANCES MOVING OUT OF THE ROCKIES AND INTO THE PLAINS WILL ALSO BE

APPROACHING. THE DRYLINE AND WARM FRONT ARE EXPECTED TO BE THE FOCUS

FOR INITIAL THUNDERSTORM DEVELOPMENT THIS AFTERNOON...WITH THE STORMS

HAVING THE POTENTIAL TO QUICKLY BECOME SEVERE AS THEY RACE

NORTHEASTWARD.

LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY THREAT... BUT THE

VERTICAL WIND PROFILE EXPECTED OVER EASTERN OKLAHOMA AND NORTHWEST

ARKANSAS BY THIS AFTERNOON AND THIS EVENING ALSO SUGGEST THAT A FEW

LONG-LIVED SUPERCELL THUNDERSTORMS COULD DEVELOP... PRODUCING A THREAT

OF TORNADOES.

THE MAIN TIME FRAME FOR SEVERE THUNDERSTORMS WILL BEGIN OVER EASTERN

OKLAHOMA BY LATE THIS AFTERNOON SPREADING INTO NORTHWEST ARKANSAS BY

THIS EVENING. THE THREAT WILL REMAIN ONGOING INTO THE NIGHT... ESPECIALLY

OVER NORTHWEST ARKANSAS AND SOUTHEAST OKLAHOMA.

EMERGENCY MANAGEMENT AGENCIES AND SPOTTER GROUPS SHOULD MONITOR THIS

WEATHER SITUATION CLOSELY THROUGH THE DAY... AND MAINTAIN A HIGH STATE OF

READINESS FOR ACTIVATION THROUGH TONIGHT.
C-18

PUBLIC INFORMATION STATEMENT

NATIONAL WEATHER SERVICE TULSA OK

110 PM CDT SUN APR 21 1996

AN OUTBREAK OF SEVERE THUNDERSTORMS AND TORNADOES IS EXPECTED ACROSS

PORTIONS OF EASTERN OKLAHOMA AND NORTHWEST ARKANSAS LATE THIS

AFTERNOON AND TONIGHT.

WATCHES...WARNINGS...SHORT TERM FORECASTS...AND STATEMENTS WILL DETAIL

THE PROGRESS OF THIS SEVERE WEATHER EPISODE. NOW...BEFORE THE STORMS

ARRIVE... IS THE TIME TO ENSURE THAT YOU ARE PREPARED FOR THE STORMY

WEATHER.

THE FIRST KEY TO BEING PREPARED IS KNOWING THE TERMINOLOGY.

A WATCH IS A FORECAST INDICATING THE POSSIBILITY OF THREATENING WEATHER. IF

A WATCH IS ISSUED FOR YOUR LOCATION REMAIN ALERT TO CONDITIONS IN YOUR

AREA... KEEP A RADIO OR TELEVISION TURNED ON AND ENSURE YOUR NOAA

WEATHER RADIO IS SET IN THE ALERT MODE.

A WARNING IS ISSUED WHEN SEVERE WEATHER IS ACTUALLY OCCURRING OR RADAR

DATA INDICATES THAT IT IS ABOUT TO OCCUR. WARNING ARE ISSUED BY COUNTIES

OR PARTS OF COUNTIES. IF A WARNING FOR SEVERE WEATHER IS ISSUED FOR YOUR

LOCATION REMEMBER THAT THREATENING CONDITIONS WILL LIKELY PASS OVER OR

NEAR WHERE YOU ARE.

WATCHES AND WARNINGS ARE ISSUED FOR TORNADOES...SEVERE

THUNDERSTORMS...AND FLASH FLOODS. TORNADO AND SEVERE THUNDERSTORM

WATCHES FOR ALL THE LOWER 48 UNITED STATES ARE ISSUED BY THE NATIONAL

WEATHER SERVICE STORM PREDICTION CENTER IN KANSAS CITY MO. TORNADO AND

SEVERE THUNDERSTORM WARNING...AS WELL AS FLASH FLOOD WATCHES AND

WARNINGS FOR EASTERN OKLAHOMA AND NORTHWEST ARKANSAS ARE ISSUED BY

THE NATIONAL WEATHER SERVICE IN TULSA.

IF A TORNADO WARNING IS ISSUED FOR YOUR AREA MOVE QUICKLY TO THE LOWEST

FLOOR POSSIBLE. STAY AWAY FROM OUTSIDE WALLS AND WINDOWS. BASEMENTS

AND STORM CELLARS OFFER THE BEST PROTECTION. IN PUBLIC BUILDINGS AVOID

LARGE ROOMS SUCH AS AUDITORIUMS... THEATERS... CAFETERIAS.. .AND

GYMNASIUMS. MOBILE HOMES SHOULD BE ABANDONED FOR NEARBY MORE

SUBSTANTIAL STRUCTURES. IF YOU LIVE IN A MOBILE HOME NOW IS THE TIME TO

SELECT WHERE YOU WOULD GO IF A TORNADO THREATENS. VEHICLES OFFER NO

PROTECTION IN A TORNADO. IF A TORNADO APPROACHES WHILE YOU ARE DRIVING

AND YOU CANNOT ESCAPE... SEEK SHELTER IN A NEARBY BUILDING. IF NO SHELTER IS

AVAILABLE LIE FLAT IN THE NEAREST DITCH OR LOW SPOT AND HOLD ON TO

SOMETHING.

IF A SEVERE THUNDERSTORM WARNING IS ISSUED FOR YOUR AREA MOVE INDOORS

AND BE READY TO SEEK SHELTER. A SEVERE THUNDERSTORM IS DEFINED AS

HAVING HAIL DIME SIZE OR GREATER AND WIND GUSTS OF 58 MPH OR MORE. IN

EXTREME CASES... SEVERE THUNDERSTORMS CAN PRODUCE WINDS TO NEAR 150

MPH AND HAIL LARGER THAN GRAPEFRUITS.
C-19

SEVERE THUNDERSTORM WARNINGS ISSUED BY THE TULSA OFFICE WILL CONTAIN

INFORMATION CONCERNING THE WIND AND HAIL POTENTIAL. WHILE THESE

CONDITIONS MAY NOT OCCUR IN ALL OF THE WARNED AREA... THEY ARE LIKELY IN

THE CORE OF THE STORM. IF WINDS OVER 70 MPH OR HAIL BIGGER THAN QUARTER

SIZE IS EXPECTED... YOU SHOULD SEEK SHELTER AS YOU WOULD FOR AN

APPROACHING TORNADO.

ALSO REMEMBER THAT TORNADOES OFTEN FORM VERY RAPIDLY FROM A SEVERE

THUNDERSTORM. IF YOU ARE IN A TORNADO WATCH... AND A SEVERE

THUNDERSTORM WARNING IS ISSUED FOR YOUR AREA YOU SHOULD KEEP A VERY

CLOSE EYE ON YOUR LOCAL CONDITIONS AND BE READY TO TAKE QUICK ACTION TO

SAVE YOUR LIFE.

WHILE HAIL AND STRONG WINDS ARE MOST OFTEN MENTIONED WHEN DESCRIBING

SEVERE STORMS... REMEMBER THAT LIGHTNING IS A THUNDERSTORMS MOST

UNDERRATED KILLER. PEOPLE OUTDOORS IN OPEN AREAS OR IN BOATS ARE AT THE

GREATEST RISK FROM LIGHTNING. LIGHTNING TENDS TO STRIKE THE TALLER

OBJECTS IN THE AREA... SO SEEKING SHELTER UNDER A TREE IS DANGEROUS. 

AUTOMOBILES OFFER GOOD PROTECTION FROM LIGHTNING... ALTHOUGH MOVING

INDOORS IS BEST. EVEN INSIDE... LIGHTNING CAN KILL BY COMING INTO THE HOME ON

PHONE LINES... PLUMBING AND ELECTRIC LINES. THEREFORE DO NOT USE THE

TELEPHONE OR OTHER HAND HELD APPLIANCES WHILE THE STORM IS OVERHEAD. BE

CAUTIOUS OF LIGHTNING BOTH BEFORE AND AFTER THE RAIN. LIGHTNING CAN STRIKE

UP TO 15 MILES FROM THE PARENT STORM. MANY PEOPLE ARE STRUCK BECAUSE

THEY STAYED OUT UNTIL THE LAST MINUTE... OR WENT OUTSIDE IMMEDIATELY AFTER

THE RAIN ENDED.

FLASH FLOODING IS A THREAT TO BOTH THOSE WHO LIVE NEAR CREEKS OR STREAMS

AND THOSE IN VEHICLES. IF YOU LIVE IN A FLOOD PRONE AREA BE READY TO MOVE

TO HIGHER GROUND WHEN A FLASH FLOOD WATCH IS POSTED... AND TAKE ACTIONS

TO PROTECT LIFE AND PROPERTY IF A FLASH FLOOD WARNING IS ISSUED. 

MOTORISTS ARE URGED TO NEVER DRIVE INTO FLOWING WATER... NO MATTER HOW

SHALLOW AND NEVER DRIVE ONTO A FLOODED ROADWAY WHEN THE DEPTH OF THE

WATER IS UNKNOWN. WHILE THE WATER MAY APPEAR SHALLOW... THE ROAD BELOW

MAY HAVE BEEN WASHED AWAY... LEAVING A MUCH DEEPER AREA OF WATER THAN

EXPECTED.

THIS SUMMARY OF SAFETY INFORMATION HAS BEEN COMPILED FOR QUICK

REFERENCE BY THE MEDIA FOR USE DURING THE UPCOMING WEATHER EVENT. RADIO

AND TELEVISION STATIONS ARE ASKED TO BREAK THIS INFORMATION INTO SHORT

PUBLIC SERVICE ANNOUNCEMENTS AND OCCASIONALLY BROADCAST THEM DURING

WATCHES... AND FREQUENTLY BROADCAST THEM DURING WARNINGS.

ZCZC OKCSVSTUL

TTAA00 KTUL 220254

OKZ074-220330

SEVERE WEATHER STATEMENT

NATIONAL WEATHER SERVICE TULSA OK

953 PM CDT SUN APR 21 1996
C-20

A TORNADO WARNING REMAINS IN EFFECT FOR HASKELL COUNTY UNTIL 1015

PM.

AT 951 PM RADAR INDICATED A POSSIBLE TORNADO BETWEEN QUINTON AND

KINTA. THE STORM IS MOVING EAST NORTHEAST AT 25 MPH. IF YOU ARE IN

OR NEAR KINTA

YOU SHOULD TAKE SHELTER NOW!
C-21

ZCZC OKCNOWTUL

TTAA00 KTUL 220258

SHORT TERM FORECAST

NATIONAL WEATHER SERVICE TULSA OK

957 PM CDT SUN APR 21 1996

ARZ019-029-OKZ070>076-220400-

CRAWFORD AR-SEBASTIAN AR-MUSKOGEE OK-MCINTOSH OK-SEQUOYAH OKPITTSBURG OK-HASKELL OK-LATIMER OK-LE FLORE OK-

.NOW...

A DANGEROUS SEVERE THUNDERSTORM... CAPABLE OF PRODUCING A TORNADO...

WILL MOVE EAST NORTHEAST FROM THE QUINTON AREA OF NORTHEAST 

PITTSBURG COUNTY ACROSS THE KINTA AND KEOTA AREAS OF HASKELL COUNTY

THROUGH 1030 PM. ANOTHER INTENSE THUNDERSTORM WILL TRACK ACROSS 

THE PORUM AND WEBBERS FALLS AREAS OF SOUTHERN MUSKOGEE COUNTY

THROUGH 1033 PM. THESE STORMS WILL TRACK ACROSS SEQUOYAH AND FAR

NORTHERN LE FLORE COUNTY BETWEEN 1030 AND 1100 PM. IF THE STORMS HOLD

TOGETHER... THEY COULD THREATEN FORT SMITH ARKANSAS AFTER 11PM.

&&

...TORNADO WARNING UNTIL 1015 PM FOR HASKELL COUNTY...

$$ 
C-22

ZCZC OKCSVSTUL

TTAA00 KTUL 220315

OKZ074-220330

SEVERE WEATHER STATEMENT

NATIONAL WEATHER SERVICE TULSA OK

1014 PM CDT SUN APR 21 1996

A TORNADO WARNING IS IN EFFECT UNTIL 1045 PM.

AT 1012 PM RADAR INDICATED A TORNADO 4 MILES SOUTHWEST OF STIGLER. THIS

TORNADO IS WRAPPED IN RAIN AND WOULD NOT BE VISIBLE. THE TORNADO IS

TRACKING TO NEAR OR JUST SOUTH OF STIGLER AND TOWARD KEOTA.

IF YOU ARE IN THE STIGLER AND KEOTA AREAS TAKE SHELTER NOW!
C-23

ZCZC OKCNOWTUL

TTAA00 KTUL 220334

SHORT TERM FORECAST

NATIONAL WEATHER SERVICE TULSA OK

1033 PM CDT SUN APR 21 1996

ARZ019-029-OKZ072-074-076-220400-

CRAWFORD AR-SEBASTIAN AR-SEQUOYAH OK-HASKELL OK-LE FLORE OK-

.NOW...

...DANGEROUS SEVERE THUNDERSTORM APPROACHING THE FORT SMITH AREA...

A VERY SEVERE THUNDERSTORM WITH A POSSIBLE TORNADO JUST NORTH OF KEOTA

IN EASTERN HASKELL COUNTY WILL TRACK EAST NORTHEAST OVER SOUTHERN

SOUTHERN SEQUOYAH AND NORTHERN LE FLORE COUNTIES...BETWEEN MULDROW

AND SPIRO THROUGH 11 PM. IF THIS STORM HOLDS TOGETHER..IT WILL AFFECT THE

FORT SMITH ARKANSAS AREA AFTER 11 PM. IN ADDITION TO TORNADOES... THIS

STORM IS CAPABLE OF PRODUCING HAIL UP TO GOLF BALL SIZE AND WINDS UP TO 70

MPH.

&&

...TORNADO WARNING UNTIL 1115 PM FOR SOUTHERN SEQUOYAH AND NORTHERN LE

FLORE COUNTIES...

$$ 
C-24

ZCZC OKCSVSTUL

TTAA00 KTUL 220337

OKZ072-074-076-220415-

SEVERE WEATHER STATEMENT

NATIONAL WEATHER SERVICE TULSA OK

1036 PM CDT SUN APR 21 1996

THIS STATEMENT IS FOR NORTHERN LE FLORE COUNTY AND HASKELL COUNTY.

AT 1033 PM RADAR INDICATED A POSSIBLE TORNADO JUST NORTH OF KEOTA... IN

ADDITION... A SECOND CIRCULATION WAS DEVELOPING FURTHER SOUTH NEAR

BOKOSHE. THIS LARGE AND DANGEROUS THUNDERSTORM WAS MOVING EAST

NORTHEAST AT 25 MPH. 

IF YOU ARE NEAR KEOTA...BOKOSHE...AND COWLINGTON YOU SHOULD BE IN A PLACE

OF SAFETY!
C-25

ZCZC OKCSVSTUL

TTAA00 KTUL 220341

OKZ076-220415-

SEVERE WEATHER STATEMENT

NATIONAL WEATHER SERVICE TULSA OK

1040 PM CDT SUN APR 21 1996

THIS STATEMENT IS FOR LE FLORE COUNTY...

AT 1033 PM SPOTTERS REPORTED A FUNNEL CLOUD OVER BOKOSHE. RADAR

INDICATED THAT A TORNADO IS DEVELOPING THERE. IF YOU ARE IN OR AROUND

BOKOSHE SEEK SHELTER NOW!
C-26

ZCZC OKCSVSTUL

TTAA00 KTUL 220350

OKZ072-076-ARZ019-029-220415-

SEVERE WEATHER STATEMENT

NATIONAL WEATHER SERVICE TULSA OK

1049 PM CDT SUN APR 21 1996

A TORNADO WARNING REMAINS IN EFFECT FOR SOUTHERN SEQUOYAH AND

NORTHERN LE FLORE COUNTY.

AT 1046 PM SPOTTERS REPORTED A FUNNEL CLOUD APPROACHING PANAMA AND

RADAR INDICATES THAT A TORNADO IS FORMING THERE. THE STORM IS MOVING EAST

NOTHEAST AT 25 MPH AND IS MOVING TOWARD POCOLA.

SPOTTERS IN MULDROW REPORTED QUARTER SIZE HAIL AT 1047 PM.

WARNINGS FOR THE FORT SMITH AND VAN BUREN AREAS MAY BE REQUIRED SOON.
C-27

ZCZC OKCSVSTUL

TTAA00 KTUL 220402

OKZ072-076-ARZ019-029-220430-

SEVERE WEATHER STATEMENT

NATIONAL WEATHER SERVICE TULSA OK

1101 PM CDT SUN APR 21 1996

THIS STATEMENT IS FOR SEQUOYAH... LE FLORE... SEBASTIAN AND CRAWFORD

COUNTIES.

A LARGE SEVERE THUNDERSTORM WAS MOVING INTO THE FORT SMITH AND VAN

BUREN AREAS. THIS STORM PRODUCED GOLFBALL SIZE HAIL IN MULDROW AT 1058

PM. 

THIS IS A DANGEROUS STORM. IF YOU LIVE IN THE FORT SMITH AND VAN BUREN

AREAS YOU SHOULD MOVE TO A PLACE OF SAFETY.
C-28

ZCZC OKCNOWTUL

TTAA00 KTUL 220412

SHORT TERM FORECAST

NATIONAL WEATHER SERVICE TULSA OK

1110 PM CDT SUN APR 21 1996

ARZ019-029-OKZ072-076-220430-

CRAWFORD AR-SEBASTIAN AR-SEQUOYAH OK-LE FLORE OK-

.NOW...

...SEVERE THUNDERSTORM WITH A POSSIBLE TORNADO MOVING INTO THE FORT

SMITH AND VAN BUREN AREAS...

A SEVERE THUNDERSTORM WITH HAIL UP TO GOLF BALL SIZE AND A POSSIBLE

TORNADO WILL MOVE ACROSS THE FORT SMITH AND VAN BUREN AREAS THROUGH

1120 PM. PERSONS IN THE PATH OF THIS DANGEROUS STORM SHOULD TAKE COVER

IMMEDIATELY!! THE STORM WILL CONTINUE EAST NORTHEASTWARD OVER SOUTHERN

CRAWFORD COUNTY THROUGH 1145 PM.

&&

...TORNADO WARNING UNTIL MIDNIHT FOR SOUTHERN CRAWFORD AND NORTHERN

SEBASTIAN COUNTIES...

$$ 
C-29

ZCZC OKCSVSTUL

TTAA00 KTUL 220415

OKZ072-ARZ019-029-220445-

SEVERE WEATHER STATEMENT

NATIONAL WEATHER SERVICE TULSA OK

1113 PM CDT SUN APR 21 1996

AT 1112 PM A FUNNEL CLOUD WAS REPORTED ALMOST TO THE GROUND IN FORT

SMITH. RADAR INDICATED THAT A TORNADO WAS DEVELOPING IN FORT SMITH. THE

TORNADO WAS MOVING NORTHEAST AT 25 MPH AND WILL MOVE TOWARD VAN BUREN. 

IF YOU ARE IN OR AROUND FORT SMITH AND VAN BUREN SEEK SHELTER NOW!
C-30

ZCZC OKCSVSTUL

TTAA00 KTUL 220423

ARZ019-029-220500-

SEVERE WEATHER STATEMENT

NATIONAL WEATHER SERVICE TULSA OK

1122 PM CDT SUN APR 21 1996

A TORNADO WARNING IS IN EFFECT FOR SOUTHERN CRAWFORD AND NORTHERN

SEBASTIAN COUNTY.

AT 1120 PM RADAR INDICATED A POSSIBLE TORNADO JUST NORTH OF VAN BUREN. 

SPOTTERS REPORTED A FUNNEL CLOUD NEAR VAN BUREN AT 1119 PM

SOME DAMAGE HAS BEEN REPORTED IN FORT SMITH. IF YOU LIVE IN THE VAN BUREN

AND ALAMA AREAS SEEK SHELTER NOW!
C-31

ZCZC OKCNOWTUL

TTAA00 KTUL 220509

SHORT TERM FORECAST

NATIONAL WEATHER SERVICE TULSA OK

1208 AM CDT MON APR 22 1996

ARZ001-002-010-011-019-220600-

BENTON AR-CARROLL AR-WASHINGTON AR-MADISON AR-CRAWFORD AR-

.NOW...

A SEVERE THUNDERSTORM WILL TRACK OVER THE ST PAUL... DUTTON... AND BOSTON

AREAS OF SOUTHERN MADISON COUNTY THROUGH 1230 AM. LARGE HAIL AND

DAMAGING WINDS ARE EXPECTED WITH THIS STORM... AND TORNADO DEVELOPMENT

MAY OCCUR. ELSEWHERE... A LARGE AREA OF RAIN AND THUNDERSTORMS WILL

CONTINUE ACROSS NORTHWEST ARKANSAS NORTH OF FORT SMITH THROUGH 1 AM.

&&

...TORNADO WARNING FOR SOUTHERN MADISON COUNTY UNTIL 1230 AM...

$$ 
Builds refered to are major AWIPS Software releases which are part of 1

the planned AWIPS incremental development

1

STATUS OF ACTIONS

December 1996

Recommendation 1.1

The ability to access and display detailed ASOS data integrated with radar and other

data sources needs to be incorporated in the Advanced Weather Information

Processing System (AWIPS).

Status: AWIPS will have access to routine and special ASOS observations with the

implementation of Build 3 by the end of 1997. Additional, direct access to ASOS 5- 1

minute data is expected by Build 6.

Recommendation 2.1

Public Information Statements are designed to be used by the media to alert the

populace to a predicted weather event. Information contained in such statements

should be concise and easy to use. 

Status: This recommendation has been provided to the Tulsa NWSFO; however, since

the implication is nationwide, NWS Headquarters needs to address the issue on a

national level, i.e. appropriate language in Weather Service Operations Manual

(WSOM) C-40.

Recommendation 2.2a

The NWS should continue to provide training to increase the level of understanding

and appropriate use of new WSR-88D products and capabilities. Each successive

software build for years to come will have new products and additional functions. 

Continuous training using various distance learning technologies appears to be an

effective method for ensuring NWS field offices have adequate knowledge of updated

products and system functions.

Status: Training on the warning decision process and the proper use of the V shear r

product was giving to the staff of Tulsa NWSFO on July 9th by the Operations Training

Branch (OTB) staff. The WSR-88D Operations Course material has been changed to

include more about the use or potential misuse of the V Shear Product and to ut r ilize

the base velocity information along with the storm relative velocity products in a

warning situation.
2

Recommendation 2.2b

The WSR-88D provides forecasters with a wide variety of products that assess the

potential severity of storms. Forecasters diagnosing severe storms should use the

system to its fullest capability by examining a representative suite of products in their

evaluation.

Status: The WSR-88D Operations Course material has been changed to include more

about the use or potential misuse of the V Shear Product and to ut r ilize the base

velocity information along with the storm relative velocity products in a warning

situation.

Recommendation 2.3

A lack of damage reports, especially at night or in sparsely populated areas, should not

play a significant role in the decision process regarding the issuance of severe weather

warnings, especially those involving tornadoes. Forecasters should issue warnings

based on the best available information derived from various technologies and reports

from trained spotters.

Status: This recommendation has been provided to the Tulsa Office.

Recommendation 2.4

Accurate, descriptive reports from trained spotters provide a valuable source of ground

truth which can enhance the interpretation of storm structure available from radar or

other remotely observed data. These reports can appear geographically inconsistent

with radar severe weather signatures for a number of reasons, including the relative

location of the weather observed to the spotter’s position. When discrepancies exist,

attempts should be made by office personnel to resolve the discrepancies or obtain

additional reports, if time allows. No spotter report should be dismissed solely on the

grounds of not coinciding with the location of a radar signature. 

Status: This recommendation has been provided to the Tulsa Office.

Recommendation 2.5

Forecasters should tailor “Call to Action” statements in dangerous situations to the

specific conditions inherent in the storm, as this statement did.

Status: No action to date.

Recommendation 2.6a

NWS should provide further clarification of the roles of personnel in spin-down WSOs

which maintain use of commissioned local warning radars.

Status: NWS Southern Region issued regionwide guidance regarding this issue on

June 19, 1996.
3

Recommendation 2.6b

NWSFO Tulsa should enhance their working relationship with the Ft. Smith WSO so

that the WSO’s expertise on the local area, including the spotter network and

community contacts, can be integrated more fully into the warning process.

Status: Tulsa staff began familarization trips to Ft. Smith WSO on June 25, 1996. A

new Meteorologist-in-Charge (MIC) reported for duty full time at Tulsa on October 21. 

The Tulsa Warning Coordination Meteorologist (WCM) has visited the Ft. Smith office

a couple of time, and the Tulsa MIC and WCM visited Ft. Smith on November 13. The

Tulsa MIC plans to have the Ft. Smith staff come to the NWSFO for additional

familiarization with the Tulsa staff.

Recommendation 3.1

The NWS should accelerate the planned transfer of administrative responsibility for the

Ft. Smith WSO from Little Rock NWSFO to Tulsa NWSFO . This transfer will facilitate

the planning and coordination of joint preparedness and hazard awareness activities.

Status: Transfer occurred on June 1, 1996.

Recommendation 4.1

The NWS should work with officials in Ft. Smith and surrounding areas to explore

methods to improve the communication of critical warning information in a timely

manner. Use of NOAA Weather Radio (NWR), two-way radio, and Emergency

Manager Weather Information Network (EMWIN) should be a priority consideration. 

Cooperative efforts between the NWS and Federal, State, and Local emergency

management agencies are essential for improving the flow of critical weather

information into the Ft. Smith and Van Buren areas.

Status: A facility for EMWIN radio transmission was identified and transmissions began

on August 17, 1996. Signal covers all of the immediate Ft. Smith area. The NWS

supplied the transmission equipment and provided a demonstration unit which has

been placed in Ft. Smith Public Library. The NWS also plans to supply four NWR

SAME receivers to selected entities in the Ft. Smith area, also on loan. Current plans

are to place the receivers in the Lavaca School (already in place), Ft. Smith 911

dispatch, Van Buren 911 dispatch, and at the Ft. Smith School Administration facility. 

The MIC at Tulsa is exploring additional possibilities, including Pagers and

enhancements to the existing HAM radio links.

Recommendation 4.2

The NWS shall provide explicit guidelines clarifying the operations of the NAWAS

regional circuits, and identifying protocols for calls within states and across state lines. 
This initiative for expansion of the NOAA Weather Radio network was 2

proposed by Vice President Gore following the Palm Sunday tornado outbreak in 1994.

4

Local offices shall conduct training and perform drills to ensure that these guidelines

are followed during warning operations. 

Status: This finding was developed just prior to publication. NWS Headquarters has

begun to determine what instructions have been provided with the NAWAS upgrade.

Recommendation 5.1

The NWS should develop additional partnership initiatives with the public and private

sector to encourage the distribution and usage of NWR.

Status: This is an ongoing activity throughout the Southern Region in response to the

Gore initiative . A number of cooperator NWR transmitters have already been 2

installed, and more are in the planning stages.