Alert archive / Arkansas / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 271, NWS Tulsa, OK

August 25, 2002Sebastian County, Arkansas

NWS Tulsa, OK issued this severe thunderstorm warning at Aug 25, 2002, 2:17 AM CDT for Sebastian County, Arkansas. It was in force for 43 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 25, 2002, 2:17 AM CDT (07:17 UTC)
Expired: Aug 25, 2002, 3:00 AM CDT
In force: 43 min
Issued by: NWS Tulsa, OK
Area: Counties, with a storm outline in the text

County Sebastian County, AR

The radar

The Western Arkansas radar (KSRX), 11 km from the middle of the area, began a volume at 07:17 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

Time	Report	Where	Remark
Aug 25, 2:54 AM CDT	Thunderstorm Wind 61 E	Ft Smith, AR	Thunderstorm winds estimated at 70 miles an hour blew down trees in the north part of Fort Smith. The trees blocked several roads.

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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Springfield, MO (KSGF), launched 00:00Z, 7.3 hours before the alert went out and 179 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 60 J/kg
Mixed-layer CIN: -160 J/kg
Mixed-layer LCL: 1536 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 59 m²/s²
0-3 km storm-relative helicity: 204 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

132 
WUUS54 KTSA 250717
SVRTUL
ARC131-250800-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TULSA OK
216 AM CDT SUN AUG 25 2002

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SEBASTIAN COUNTY IN WEST CENTRAL ARKANSAS

* UNTIL 300 AM CDT

* AT 216 AM CDT...DOPPLER RADAR INDICATED SEVERE THUNDERSTORMS ALONG
  A LINE EXTENDING FROM 25 MILES NORTH OF LAVACA TO 15 MILES
  NORTHEAST OF FORT SMITH TO 9 MILES NORTH OF FORT SMITH...MOVING
  SOUTHEAST AT 40 MPH.

* SOME LOCATIONS NEAR THE PATH OF THESE STORMS INCLUDE...FORT
  SMITH...HACKETT...GREENWOOD...BARLING...LAVACA...BURNVILLE...
  EXCELSIOR...BONANZA...FT CHAFFEE...JENNY LIND AND BLOOMER.

WIND GUSTS TO 65 MPH CAN BE EXPECTED IN THE WARNED AREA. STAY 
INDOORS AND AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

BE ALERT FOR RAPIDLY CHANGING WEATHER CONDITIONS AS STORMS APPROACH 
AND LISTEN CLOSELY FOR FURTHER INFORMATION.

LAT...LON 3541 9426 3545 9445 3512 9444 3517 9405
          3544 9408

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 Aug 24, 9:32 PM CDT, 4 hours 45 minutes earlier.

Area forecast discussion, Aug 24, 9:32 PM CDT, 4 hours 45 minutes before

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
930 PM SAT AUG 24 2002

TRICKY FIRST PERIOD AS FAR AS POPS GO. SURFACE BOUNDARY THIS
EVENING EXTENDS FROM WEST CENTRAL TO SE OK. LOOKS LIKE THE MAIN
PLAYER FOR SRN ZONES TONIGHT MAY BE STORMS CURRENTLY ACROSS THE TX
PANHANDLE/NW OK THAT HAD DEVELOPED IN THE VICINITY OF THE BOUNDARY
AND ARE PUSHING TO THE EAST SOUTHEAST. OTHER STORMS...MORE ELEVATED
IN NATURE HAVE DEVELOPED ACROSS KANSAS AND MISSOURI THOUGH CURRENTLY
REMAIN NORTH OF THE FA. WILL LEAVE POPS AS THEY ARE GIVEN CURRENT
RADAR TRENDS AND PROXIMITY OF BOUNDARY. CURRENTLY ADVERTISED LOWS
LOOK REASONABLE. WILL NOT ISSUE AN UPDATE AT THIS TIME...THOUGH WILL
MONITOR TEMPERATURE AND CONVECTIVE TRENDS FOR POSSIBLE UPDATE
TOWARDS MIDNIGHT.

FORECAST ID= 23

.TSA...
AR...NONE.
OK...NONE.

In the hours before

Special weather statement, Aug 24, 8:45 PM CDT, 5 hours 32 minutes before

ARZ001-002-010-011-019-020-029-OKZ049-053>076-251200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE TULSA OK
845 PM CDT SAT AUG 24 2002

...CHANCE OF SEVERE THUNDERSTORMS TONIGHT...

A STATIONARY SURFACE BOUNDARY EXTENDED FROM NEAR OKLAHOMA CITY TO
JUST NORTH OF MCALESTER TO SOUTH OF FORT SMITH. SCATTERED
THUNDERSTORMS WERE BEGINNING TO DEVELOP NEAR THE BOUNDARY ACROSS
WESTERN AND CENTRAL OKLAHOMA THIS EVENING. SCATTERED TO NUMEROUS
THUNDERSTORMS ARE EXPECTED TO DEVELOP NEAR THE BOUNDARY ACROSS
EASTERN OKLAHOMA LATER THIS EVENING AS LIFTING INCREASES AHEAD OF AN
UPPER LEVEL SYSTEM.

A FEW OF THE THUNDERSTORMS...ESPECIALLY IN AREAS SOUTH OF A LINE
FROM TULSA TO FORT SMITH...COULD BECOME SEVERE TONIGHT AND PRODUCE
LARGE HAIL AND DAMAGING WINDS. THE AIRMASS IS SLIGHTLY MORE STABLE
IN AREAS NORTH OF A TULSA TO FORT SMITH LINE...SO LESS INTENSE
THUNDERSTORMS ARE FORECAST IN THESE AREAS.

.SPOTTER ACTIVATION...
SPOTTER ACTIVATION MAY BE NEEDED BY MIDNIGHT ACROSS PARTS OF
EASTERN OKLAHOMA AND WESTERN ARKANSAS.

.DISCUSSION...
CONVECTIVE DEVELOPMENT IS EXPECTED BY MIDNIGHT AS WARM ADVECTION
LIFT INCREASES ALONG AND NORTH OF THE SURFACE BOUNDARY. ELEVATED
INSTABILITIES OF 2500 J/KG AND MID LEVEL NORTHWESTERLY WINDS
INCREASING TO OVER 30 KNOTS SUPPORT THE POTENTIAL FOR SEVERE
THUNDERSTORMS. MARGINALLY SEVERE HAIL WILL BE POSSIBLE WITH SOME OF
THE THUNDERSTORMS...BUT THE PRIMARY SEVERE WEATHER THREAT WILL BE
DAMAGING STRAIGHT LINE WINDS.

STRONG DIVERGENCE IN THE LEFT FRONT QUADRANT OF AN 80 KNOT UPPER JET
WILL MOVE ACROSS EXTREME NORTHERN OKLAHOMA AND THE NORTHWEST CORNER
OF ARKANSAS TONIGHT. THIS UPPER SUPPORT IS NORMALLY FAVORABLE FOR
SEVERE THUNDERSTORM DEVELOPMENT...BUT INSTABILITY IS LOWER IN THIS
AREA SINCE EARLIER CONVECTION HAD A STABILIZING EFFECT. ISOLATED
SEVERE THUNDERSTORMS WILL STILL BE POSSIBLE...BUT THE MORE ORGANIZED
ACTIVITY IS EXPECTED TO REMAIN FURTHER SOUTH NEAR THE SURFACE
BOUNDARY.

RISK TABLE
VALID THROUGH 1200 UTC SUNDAY

AREA 1...ALONG AND SOUTH OF A LINE FROM TULSA TO FORT SMITH
THUNDERSTORM PROBABILITY...90
SEVERE PROBABILITY IF STORMS OCCUR...50
SIGNIFICANT SEVERE PROBABILITY IF STORMS OCCUR...30

AREA 2...NORTH OF A LINE FROM TULSA TO FORT SMITH
THUNDERSTORM PROBABILITY...100
SEVERE PROBABILITY IF STORMS OCCUR...20
SIGNIFICANT SEVERE PROBABILITY IF STORMS OCCUR...10

RISK AREAS DEFINE THE GREATEST RISK. PROBABILITIES ARE IN PERCENT.
SIGNIFICANT SEVERE IS DEFINED AS F1 OR GREATER WIND/TORNADO DAMAGE
AND/OR GOLFBALL SIZE HAIL OR LARGER.

.OTHER HAZARDS...
LOCALLY HEAVY RAINFALL IS POSSIBLE TONIGHT AND EARLY SUNDAY MORNING
AS SEVERAL ROUNDS OF THUNDERSTORMS AFFECT THE AREA.

RELATED GRAPHICAL INFORMATION CAN BE FOUND AT:
WWW.SRH.NOAA.GOV/TULSA

Local storm report, Aug 25, 1:13 AM CDT, 1 hour 4 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
113 AM CDT SUN AUG 25 2002

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1030 PM    SKEDEE                    OK   .88 INCH HAIL
08/24/02   PAWNEE                         REPORTED BY
                                          PUBLIC

1145 PM    OILTON                    OK   .88 INCH HAIL
08/24/02   CREEK                          REPORTED BY
                                          PUBLIC

1220 AM    OILTON                    OK   1.00 INCH HAIL
08/25/02   CREEK                          REPORTED BY
                                          SPOTTERS

1220 AM    6 ESE OILTON              OK   66 MPH TSTM WIND GUST
08/25/02   CREEK                          RECORDED BY OKLAHOMA
                                          MESONET

1240 AM    DRUMRIGHT                 OK   WIND DAMAGE
08/25/02   CREEK                          TREES BLOWN DOWN.
                                          REPORTED
                                          BY OKLAHOMA HIGHWAY
                                          PATROL

1258 AM    5 NW BRISTOW              OK   1.25 INCH HAIL
08/25/02   CREEK                          REPORTED BY
                                          SPOTTERS

Local storm report, Aug 25, 1:51 AM CDT, 26 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
151 AM CDT SUN AUG 25 2002

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0128 AM    1 N DEPEW                 OK   1.75 INCH HAIL
08/25/02   CREEK                          REPORTED BY
                                          SPOTTERS

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 25, 2:02 AM CDT	Severe Thunderstorm Warning	TSA	Crawford	43 min
Aug 25, 2:25 AM CDT	Severe Thunderstorm Warning	TSA	Franklin	35 min
Aug 25, 2:50 AM CDT	Severe Thunderstorm Warning	TSA	Franklin, Sebastian	40 min

Nearby

Severe Thunderstorm Warnings in Arkansas, 2002 Every severe thunderstorm warning in 2002

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.