Severe Thunderstorm Warning 279, NWS Tulsa, OK

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
920 PM CDT WED SEP 18 2002

CURRENT CONVECTION CONTINUES TO MOVE TO THE NORHTEAST AND IS MAKING
ONLY SLOW PROGRESS TO THE EAST.  EXTRAPOLATION INDICATES BY 11 PM
THE LINE WILL REACH FROM NORTHERN NOWATA COUNTY TO SOUTHEAST OSAGE
AND WESTERN CREEK.  UPPER FLOW WILL REMAIN SOUTHWEST AS UPPER TROF
CONTINUES TO DIG TO OUR WEST.  THAT WILL KEEP THE STORM MOTION FROM
THE SOUTHWEST AND LIMIT THE EASTWARD PROGRESSION TO MAINLY
DEVELOPMENT ALONG THE TSTM GUST FRONTS.  TSTORMS OVER WEST TEXAS
LIKELY RESPONDING TO THE MAIN UPPER LOW MOVING EAST.  THE TROF WILL
BE IN THE TX PHNDL BY 18Z THURSDAY...WITH STRONG DYNAMICS THROUGH
CENTRAL OK...AND WILL ALLOW THE COLDFRONT TO START MOVING EASTWARD.
EXPECT THE CURRENT ACTIVITY WILL REMAIN ONLY MARGINALLY
SEVERE...WITH SECOND SURGE OF STRONG STORMS EARLY IN THE MORNING
ALONG AND JUST AHEAD OF THE COLDFRONT...ENANCED WITH THE APPROACHING
500MB TROF.

WILL MAKE MINOR ADJUSTMENTS TO THE POPS TO REFLECT CURRENT
THINKING.  NOT INCLINED TO CHANGE ANY LOW TEMPS...EXCEPT FOR RAIN
COOLED AREAS.

FORECAST ID = 02

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

ARZ001-002-010-011-019-020-029-OKZ049-053>076-191100-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
1125 PM CDT WED SEP 18 2002

...THERE IS A CHANCE OF SEVERE THUNDERSTORMS OVER EASTERN
   OKLAHOMA TONIGHT...
...SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS A LARGE PART OF EASTERN
   OKLAHOMA AND NORTHWEST ARKANSAS THURSDAY...

THE SEVERE THUNDERSTORM THREAT OVER NORTHEAST OKLAHOMA HAS
LESSENED...BUT IS NOT COMPLETELY GONE.  THE ATMOSPHERE HAS BECOME
MORE STABLE AND HAS ALLOWED MOST THUNDERSTORMS TO WEAKEN AT THIS
TIME.  HOWEVER...ISOLATED THUNDERSTORMS MAY STILL BECOME SEVERE AT
ANY TIME AND WILL BE MONITORED CLOSELY.

.SPOTTER ACTIVATION...
SPOTTER ACTIVATION MAY STILL BE REQUIRED TONIGHT OVER ANY PART OF
EASTERN OKLAHOMA.  AT THIS TIME...SEVERE THUNDERSTORMS ARE NOT
EXPECTED TO REACH NORTHWEST ARKANSAS BEFORE 6 AM. SPOTTER ACTIVATION
MAY BE REQUIRED OVER ALL OF EASTERN OKLAHOMA AND NORTHWEST ARKANSAS
DURING THE DAY THURSDAY.

.DISCUSSION...
THUNDERSTORMS OVER NORTH CENTRAL AND NORTHEAST OKLAHOMA CONTINUE TO
MOVE NORTHEAST AND ARE BEGINNING TO TRACK ACROSS RAIN COOLED AIR...
WHICH HAS ALLOWED MOST OF THE STORMS TO WEAKEN.  HOWEVER...ANY
THUNDERSTORMS MOVING ALONG THE SOUTHERN EDGE OF THE EXISTING RAIN
AREAS WILL BE CAPABLE OF BECOMING...OR REMAINING SEVERE.  OTHER
STRONG THUNDERSTORMS IN SOUTHWEST OKLAHOMA ARE MOVING TO THE EAST
AND COULD REACH PITTSBURG...PUSHMATAHA...AND CHOCTAW COUNTIES
BETWEEN 2 AND 4 AM...THEN SWEEP ACROSS MUCH OF SOUTHEAST OKLAHOMA
BY 6 AM.  THE PRIMARY THREAT FROM THESE STORMS WILL BE WIND AND
HAIL.

THREAT TABLE
VALID THROUGH 1200 UTC THURSDAY

AREA 1...ALONG AND WEST OF A LINE FROM MIAMI TO POTEAU TO HUGO
THUNDERSTORM PROBABILITY...70
SEVERE PROBABILITY IF STORMS OCCUR...80
SIGNIFICANT SEVERE PROBABILITY IF STORMS OCCUR...30

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

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

ARZ001-002-010-011-019-020-029-OKZ049-053>076-191100-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
1125 PM CDT WED SEP 18 2002

...THERE IS A CHANCE OF SEVERE THUNDERSTORMS OVER EASTERN
   OKLAHOMA TONIGHT...
...THERE IS A SLIGHT CHANCE OF SEVERE THUNDERSTORMS OVER NORTHWEST
   ARKANSAS...
...SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS A LARGE PART OF EASTERN
   OKLAHOMA AND NORTHWEST ARKANSAS THURSDAY...

THE SEVERE THUNDERSTORM THREAT OVER NORTHEAST OKLAHOMA HAS
LESSENED...BUT IS NOT COMPLETELY GONE.  THE ATMOSPHERE HAS BECOME
MORE STABLE AND HAS ALLOWED MOST THUNDERSTORMS TO WEAKEN AT THIS
TIME.  HOWEVER...ISOLATED THUNDERSTORMS MAY STILL BECOME SEVERE AT
ANY TIME AND WILL BE MONITORED CLOSELY.

STRONG THUNDERSTORMS OVER SOUTHWEST OKLAHOMA AND BEGINNING TO
ACCELERATE TO THE EAST AND ARE EXPECTED TO MOVE INTO SOUTHEAST
OKLAHOMA AFTER 2 AM.  THESE STORMS ARE EXPECTED TO MOVE INTO
NORTHWEST ARKANSAS AFTER 3 AM.  SOME OF THESE STORMS MAY BE SEVERE.

.SPOTTER ACTIVATION...
SPOTTER ACTIVATION MAY STILL BE REQUIRED TONIGHT OVER ANY PART OF
EASTERN OKLAHOMA.  SPOTTER ACTIVATION MAY BE REQUIRED OVER NORTHWEST
ARKANSAS AFTER 3 AM.

.DISCUSSION...
THUNDERSTORMS OVER NORTH CENTRAL AND NORTHEAST OKLAHOMA CONTINUE TO
MOVE NORTHEAST AND ARE BEGINNING TO TRACK ACROSS RAIN COOLED AIR...
WHICH HAS ALLOWED MOST OF THE STORMS TO WEAKEN.  HOWEVER...ANY
THUNDERSTORMS MOVING ALONG THE SOUTHERN EDGE OF THE EXISTING RAIN
AREAS WILL BE CAPABLE OF BECOMING...OR REMAINING SEVERE.  OTHER
STRONG THUNDERSTORMS IN SOUTHWEST OKLAHOMA ARE MOVING TO THE EAST
AND COULD REACH PITTSBURG...PUSHMATAHA...AND CHOCTAW COUNTIES
BETWEEN 2 AND 4 AM...THEN SWEEP EAST INTO NORTHWEST ARKANSAS BEFORE
6 AM.  THE AIRMASS OVER SOUTHEAST OKLAHOMA REMAINS UNSTABLE AND MAY
HELP STORMS BECOME OR REMAIN SEVERE LATER TONIGHT.  THE PRIMARY
THREAT FROM THESE STORMS WILL BE WIND AND HAIL.

THREAT TABLE
VALID THROUGH 1200 UTC THURSDAY

AREA 1...ALONG AND WEST OF A LINE FROM MIAMI TO POTEAU TO HUGO
THUNDERSTORM PROBABILITY...80
SEVERE PROBABILITY IF STORMS OCCUR...80
SIGNIFICANT SEVERE PROBABILITY IF STORMS OCCUR...30

AREA 2...ALONG AND EAST OF A LINE FROM MIAMI TO POTEAU TO HUGO
THUNDERSTORM PROBABILITY...70 PERCENT
SEVERE PROBABILITY IF STORMS OCCUR...50
SIGNIFICANT SEVERE PROBABILITY IF STORMS OCCUR...20

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

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