Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 129, NWS Tulsa, OK

April 22, 1999Sequoyah County, Oklahoma; Crawford County, Arkansas

NWS Tulsa, OK issued this severe thunderstorm warning at Apr 22, 1999, 10:02 PM CDT for Sequoyah County, Oklahoma; Crawford County, Arkansas. It was in force for 43 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Apr 22, 1999, 10:02 PM CDT (03:02 UTC)
Expired
Apr 22, 1999, 10:45 PM CDT
In force
43 min
Issued by
NWS Tulsa, OK
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Crawford County, AR, Sequoyah County, OK

The radar

The Western Arkansas radar (KSRX), 31 km from the middle of the area, began a volume at 03:03 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Apr 22, 10:20 PM CDTHail 0.75Natural Dam, AR

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 22, 9:00 PM CDTSevere Thunderstorm WatchSPC4 hr

The nearest sounding before it

Springfield, MO (KSGF), launched 00:00Z, 3.0 hours before the alert went out and 164 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Springfield, MO at 00:00Z on 1999-04-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 316 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Springfield, MO at 00:00Z on 1999-04-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 326 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
316 J/kg
Mixed-layer CIN
-172 J/kg
Mixed-layer LCL
823 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
326 m²/s²
0-3 km storm-relative helicity
336 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.8

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tulsa, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 22, 8:55 PM CDT, 1 hour 7 minutes earlier.

Area forecast discussion, Apr 22, 8:55 PM CDT, 1 hour 7 minutes before
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
855 PM CDT THU APR 22 1999

LINE HAS SLOWED ITS SOUTHWARD PROGRESSION AND STORMS MAY BE ON A
WEAKENING TREND. UPDATED ZONES TO ADJUST POPS AND HEADLINES FOR
SEVERE WATCH. CONSIDERED FLASH FLOOD WATCH...BUT WARNINGS ALREADY
BEING ISSUED AND HEAVY RAIN THREAT MAY DIMINISH IN NEXT HOUR OR SO...
BUT DID MENTION HEAVY RAINS IN ZONES FROM EC OK INTO NW ARK. /13

/13
AR...NONE.
OK...NONE.

In the hours before

Special weather statement, Apr 22, 7:45 PM CDT, 2 hours 17 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-230200-

SPECIAL WEATHER STATEMENT...CORRECTED TIMES AND EXPIRATION
NATIONAL WEATHER SERVICE TULSA OK
745 PM CDT THU APR 22 1999

TORNADO WATCH 166 REMAINS IN EFFECT UNTIL 9PM FOR THE FOLLOWING
COUNTIES:

IN NORTHEAST OKLAHOMA
OKMULGEE...MUSKOGEE...WAGONER...CHEROKEE...ADAIR...DELAWARE AND MAYES

IN NORTHWEST ARKANSAS
BENTON...WASHINGTON AND CRAWFORD

THE TORNADO WATCH HAS BEEN CANCELED FOR THE FOLLOWING COUNTIES:

IN NORTHEAST OKLAHOMA
WASHINGTON...NOWATA...CRAIG...OTTAWA...CREEK...TULSA AND ROGERS.

AT 740 PM...RADAR INDICATED THE LINE OF STRONG TO SEVERE THUNDERSTORMS
HAD MOVED SOUTHEASTWARD INTO FAR NORTHWEST ARKANSAS AND EASTCENTRAL
OKLAHOMA. THE THREAT FOR SEVERE STORMS AND TORNADOES WILL CONTINUE
UNTIL 9PM IN THE WATCH AREA.

IF THREATENING WEATHER APPROACHES MOVE TO SAFE SHELTER.
Special weather statement, Apr 22, 7:45 PM CDT, 2 hours 17 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-230200-

SPECIAL WEATHER STATEMENT...CORRECTED TIMES AND EXPIRATION
NATIONAL WEATHER SERVICE TULSA OK
745 PM CDT THU APR 22 1999

TORNADO WATCH 166 REMAINS IN EFFECT UNTIL 9PM FOR THE FOLLOWING
COUNTIES:

IN NORTHEAST OKLAHOMA
OKMULGEE...MUSKOGEE...WAGONER...CHEROKEE...ADAIR...DELAWARE AND MAYES

IN NORTHWEST ARKANSAS
BENTON...WASHINGTON AND CRAWFORD

THE TORNADO WATCH HAS BEEN CANCELED FOR THE FOLLOWING COUNTIES:

IN NORTHEAST OKLAHOMA
WASHINGTON...NOWATA...CRAIG...OTTAWA...CREEK...TULSA AND ROGERS.

AT 740 PM...RADAR INDICATED THE LINE OF STRONG TO SEVERE THUNDERSTORMS
HAD MOVED SOUTHEASTWARD INTO FAR NORTHWEST ARKANSAS AND EASTCENTRAL
OKLAHOMA. THE THREAT FOR SEVERE STORMS AND TORNADOES WILL CONTINUE
UNTIL 9PM IN THE WATCH AREA.

IF THREATENING WEATHER APPROACHES MOVE TO SAFE SHELTER.
Special weather statement, Apr 22, 8:55 PM CDT, 1 hour 7 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-230600-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TULSA OK
855 PM CDT THU APR 22 1999

TORNADO WATCH 166 WILL BE ALLOWED TO EXPIRE AT 9PM.

SEVERE THUNDERSTORM WATCH NUMBER 168 IS IN EFFECT UNTIL 1AM FOR
THE FOLLOW COUNTIES:

IN EASTERN OKLAHOMA...
ADAIR...CHEROKEE...MCINTOSH...MUSKOGEE...OKFUSKEE...
OKMULGEE...SEQUOYAH...PITTSBURG...HASKELL...LATIMER
AND LE FLORE.

IN NORTHWEST ARKANSAS...
BENTON...MADISON...CARROLL...CRAWFORD...WASHINGTON...FRANKLIN AND
SEBASTIAN.

A LINE OF STRONG TO SEVERE THUNDERSTORMS WILL CONTINUE TO SLOWLY SAG
SOUTHWARD THROUGH NORTHWEST ARKANSAS AND EASTCENTRAL OKLAHOMA.
LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH THE STORMS IN THE
WATCH AREA.

IF THREATENING WEATHER APPROACHES MOVE TO SAFE SHELTER.
Special weather statement, Apr 22, 8:55 PM CDT, 1 hour 7 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-230600-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TULSA OK
855 PM CDT THU APR 22 1999

TORNADO WATCH 166 WILL BE ALLOWED TO EXPIRE AT 9PM.

SEVERE THUNDERSTORM WATCH NUMBER 168 IS IN EFFECT UNTIL 1AM FOR
THE FOLLOW COUNTIES:

IN EASTERN OKLAHOMA...
ADAIR...CHEROKEE...MCINTOSH...MUSKOGEE...OKFUSKEE...
OKMULGEE...SEQUOYAH...PITTSBURG...HASKELL...LATIMER
AND LE FLORE.

IN NORTHWEST ARKANSAS...
BENTON...MADISON...CARROLL...CRAWFORD...WASHINGTON...FRANKLIN AND
SEBASTIAN.

A LINE OF STRONG TO SEVERE THUNDERSTORMS WILL CONTINUE TO SLOWLY SAG
SOUTHWARD THROUGH NORTHWEST ARKANSAS AND EASTCENTRAL OKLAHOMA.
LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH THE STORMS IN THE
WATCH AREA.

IF THREATENING WEATHER APPROACHES MOVE TO SAFE SHELTER.
Special weather statement, Apr 22, 9:20 PM CDT, 42 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-231200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
920 PM CDT THU APR 22 1999

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PARTS OF SOUTHEAST OKLAHOMA
AND NORTHWEST ARKANSAS UNTIL 1 AM.

.SYNOPSIS...
AT 920 PM...A 30 MILE WIDE BAND OF STRONG TO SEVERE THUNDERSTORMS
EXTENDED FROM NEAR FAYETTEVILLE TO OKEMAH IN SOUTHERN OKFUSKEE COUNTY.
THESE THUNDERSTORMS WERE ALONG A COLD FRONT THAT IS FORECAST TO SAG
SLOWLY SOUTHEAST INTO PARTS OF SOUTHEAST OKLAHOMA AND WEST CENTRAL
ARKANSAS THROUGH THE EARLY MORNING.

.DISCUSSION...
THE LINE OF THUNDERSTORMS ACROSS EAST CENTRAL OKLAHOMA AND NORTHWEST
ARKANSAS IS EXPECTED TO GRADUALLY WEAKEN THROUGH 1 AM AS THEY ENCOUNTER
A MORE CAPPED AIRMASS OVER SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS.
HOWEVER...ISOLATED SEVERE THUNDERSTORMS CAPABLE OF PRODUCING LARGE HAIL
AND DAMAGING WINDS WILL BE POSSIBLE MAINLY THROUGH MIDNIGHT.  FAVORABLE
WIND PROFILES WILL ALSO SUPPORT THE DEVELOPMENT OF A TORNADO OR
TWO...MAINLY OVER NORTHWEST ARKANSAS.

IN ADDITION...DUE TO THE VERY SLOW MOVEMENT OF THIS LINE...LOCALIZED
HEAVY RAINFALL AND FLASH FLOODING IS LIKELY AS THIS LINE OF
THUNDERSTORMS SAGS INTO SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS.

.EMERGENCY MANAGEMENT AGENCY AND SPOTTER ACTIVATION...
SPOTTER ACTIVATION IS IN EFFECT.  HOWEVER NO SPOTTER ACTIVATION IS
EXPECTED BEYOND 1 AM.
Special weather statement, Apr 22, 9:20 PM CDT, 42 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-231200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
920 PM CDT THU APR 22 1999

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PARTS OF SOUTHEAST OKLAHOMA
AND NORTHWEST ARKANSAS UNTIL 1 AM.

.SYNOPSIS...
AT 920 PM...A 30 MILE WIDE BAND OF STRONG TO SEVERE THUNDERSTORMS
EXTENDED FROM NEAR FAYETTEVILLE TO OKEMAH IN SOUTHERN OKFUSKEE COUNTY.
THESE THUNDERSTORMS WERE ALONG A COLD FRONT THAT IS FORECAST TO SAG
SLOWLY SOUTHEAST INTO PARTS OF SOUTHEAST OKLAHOMA AND WEST CENTRAL
ARKANSAS THROUGH THE EARLY MORNING.

.DISCUSSION...
THE LINE OF THUNDERSTORMS ACROSS EAST CENTRAL OKLAHOMA AND NORTHWEST
ARKANSAS IS EXPECTED TO GRADUALLY WEAKEN THROUGH 1 AM AS THEY ENCOUNTER
A MORE CAPPED AIRMASS OVER SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS.
HOWEVER...ISOLATED SEVERE THUNDERSTORMS CAPABLE OF PRODUCING LARGE HAIL
AND DAMAGING WINDS WILL BE POSSIBLE MAINLY THROUGH MIDNIGHT.  FAVORABLE
WIND PROFILES WILL ALSO SUPPORT THE DEVELOPMENT OF A TORNADO OR
TWO...MAINLY OVER NORTHWEST ARKANSAS.

IN ADDITION...DUE TO THE VERY SLOW MOVEMENT OF THIS LINE...LOCALIZED
HEAVY RAINFALL AND FLASH FLOODING IS LIKELY AS THIS LINE OF
THUNDERSTORMS SAGS INTO SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS.

.EMERGENCY MANAGEMENT AGENCY AND SPOTTER ACTIVATION...
SPOTTER ACTIVATION IS IN EFFECT.  HOWEVER NO SPOTTER ACTIVATION IS
EXPECTED BEYOND 1 AM.

The office that day

Everything else NWS Tulsa, OK issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 22, 7:06 PM CDTTornado WarningTSACherokee, Wagoner54 min
Apr 22, 7:10 PM CDTSevere Thunderstorm WarningTSAMuskogee, Okmulgee35 min
Apr 22, 7:39 PM CDTSevere Thunderstorm WarningTSAMuskogee51 min
Apr 22, 7:50 PM CDTSevere Thunderstorm WarningTSAMcIntosh, Okmulgee40 min
Apr 22, 7:55 PM CDTFlash Flood WarningTSACherokee3 hr
Apr 22, 7:58 PM CDTSevere Thunderstorm WarningTSAAdair, Cherokee47 min
Apr 22, 8:16 PM CDTSevere Thunderstorm WarningTSAOkfuskee, Okmulgee29 min
Apr 22, 8:28 PM CDTSevere Thunderstorm WarningTSAMcIntosh, Muskogee47 min
Apr 22, 8:33 PM CDTFlash Flood WarningTSAOkfuskee, Okmulgee3 hr
Apr 22, 8:33 PM CDTFlash Flood WarningTSAMuskogee3 hr
Apr 22, 8:44 PM CDTSevere Thunderstorm WarningTSAAdair46 min
Apr 22, 9:02 PM CDTSevere Thunderstorm WarningTSACherokee28 min
Apr 22, 9:27 PM CDTSevere Thunderstorm WarningTSAAdair, Cherokee, Sequoyah33 min
Apr 22, 9:29 PM CDTSevere Thunderstorm WarningTSAMcIntosh, Okfuskee46 min
Apr 22, 10:10 PM CDTSevere Thunderstorm WarningTSAMcIntosh, Pittsburg50 min
Apr 22, 10:41 PM CDTFlash Flood WarningTSAMcIntosh64 min
Apr 22, 11:23 PM CDTSevere Thunderstorm WarningTSAPittsburg37 min
Apr 23, 12:26 AM CDTSevere Thunderstorm WarningTSAHaskell34 min
Apr 22, 7:15 PM CDTSevere Thunderstorm WarningTSABenton30 min
Apr 22, 8:08 PM CDTSevere Thunderstorm WarningTSABenton, Washington37 min
Apr 22, 8:23 PM CDTTornado WarningTSAWashington22 min
Apr 22, 9:32 PM CDTSevere Thunderstorm WarningTSAWashington28 min
Apr 22, 9:58 PM CDTSevere Thunderstorm WarningTSAWashington32 min
Apr 22, 10:30 PM CDTSevere Thunderstorm WarningTSAFranklin, Madison45 min
Apr 22, 10:45 PM CDTSevere Thunderstorm WarningTSACrawford30 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 1999Severe Thunderstorm Warnings in Arkansas, 1999Every severe thunderstorm warning in 1999

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.