Hail and Damaging Wind in Oklahoma, April 14, 2001

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
1040 AM CDT SAT APR 14 2001

CONVECTION CONTINUES TO MOVE ENE ACROSS SOUTHEAST OKLAHOMA AND INTO
NORTHWEST ARKANSAS THIS MORNING. THIS ACTIVITY IS EXPECTED TO
GRADUALLY DIMINISH AS IT MOVES TOWARD DRIER AIR AND AWAY FROM THE
NORTHERN TEXAS SURFACE BOUNDARY. THERE COULD STILL BE SOME ACTIVE
CONVECTION AND STRONG STORMS NEAR THE RED RIVER THROUGH THE
AFTERNOON HOURS...BUT WIDESPREAD CLOUD COVER MAY LIMIT INSTABILITY
IN THAT AREA.

CONVECTIVE DEVELOPMENT LATER THIS AFTERNOON AND OVERNIGHT IS STILL
DIFFICULT TO FORECAST WITH SURFACE BOUNDARIES...CLOUD COVER...AND
UPPER SUPPORT ALL PLAYING KEY ROLES IN FORECAST. CURRENT FORECAST
HAS CHANCE OR LIKELY POPS IN ALL ZONES FOR TONIGHT...WHICH SEEMS
REASONABLE BASED ON CURRENT TRENDS.

WILL SEND AN UPDATED ZONE PACKAGE BY 1115 AM TO CLEAN UP FIRST
PERIOD WORDING IN ZONES. MAY ALSO ADJUST POPS IN SOUTHERN ZONES
BASED ON RADAR TRENDS. WILL NOT MAKE ANY CHANGES TO LATER PERIODS OF
FORECAST.

FCSTID = 9

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

ARZ001-002-010-011-019-020-029-OKZ049-053>076-151100-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
120 PM CDT SAT APR 14 2001

...A FEW SEVERE STORMS POSSIBLE THROUGH TONIGHT IN NORTHEAST
OKLAHOMA AND FAR NORTHWEST ARKANSAS...MAINLY NORTH OF A TULSA TO
FAYETTEVILLE LINE...

SURFACE LOW PRESSURE WITH A WARM FRONT THAT EXTENDED FROM NORTHWEST
OKLAHOMA AND SOUTHERN KANSAS WILL CONTINUE TO LIFT NORTH IN CENTRAL
KANSAS THIS AFTERNOON. A SECOND SURFACE BOUNDARY WAS LOCATED JUST
SOUTH OF THE RED RIVER. AS AN UPPER LEVEL SYSTEM MOVES THROUGH THE
REGION TONIGHT... THE FRONT ACROSS KANSAS WILL MOVE SOUTHWARD AS A
COLD FRONT INTO OKLAHOMA. BY SUNDAY MORNING...THE SURFACE FRONT
WILL BE ACROSS ARKANSAS AND EXTENDING SOUTHWEST ACROSS NORTHERN
TEXAS.

THUNDERSTORMS HAVE CONTINUED TO DEVELOP AND MOVE EAST ACROSS
SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS IN ASSOCIATION WITH THE
SURFACE BOUNDARY NEAR THE RED RIVER. THESE STORMS ARE EXPECTED TO
DECREASE IN AREAL COVERAGE THIS AFTERNOON.

THUNDERSTORMS ARE EXPECTED TO DEVELOP NEAR THE FRONT...FROM CENTRAL
KANSAS TO WESTERN OKLAHOMA LATE THIS AFTERNOON OR THIS EVENING. AS
THE FRONT SAGS SOUTHWARD...STRONG TO SEVERE STORMS MAY MOVE INTO
NORTHEAST OKLAHOMA NORTHWEST ARKANSAS TONIGHT. THE MAIN THREATS FROM
THE STORMS WILL BE LARGE HAIL AND DAMAGING WINDS. THE THREAT FOR
TORNADOES WOULD BE MAINLY IN KANSAS THIS EVENING.

.SPOTTER ACTIVATION...
SPOTTER ACTIVATION MAY BE NEEDED THROUGH TONIGHT IN NORTHEAST
OKLAHOMA AND NORTHWEST ARKANSAS.

.DISCUSSION...
SUPERCELL THUNDERSTORMS MAY DEVELOP WEST AND NORTHWEST OF THE AREA
THIS EVENING WHERE CAPES OF 2500-3000 J/KG AND STRONG VERTICAL WIND
SHEAR WILL BE IN PLACE. ANY STORMS THAT DEVELOP WILL TRACK TO THE
EAST OR SOUTHEAST TOWARDS NORTHEAST OKLAHOMA TONIGHT. HOWEVER...WITH
THE LOSS OF DAYTIME HEATING THE STORMS ARE EXPECTED TO LOSE SOME
INTENSITY WITH THE THREAT FOR SUPERCELLS DIMINSHING AS THEY APPROACH
NORTHEAST OKLAHOMA TONIGHT.

THREAT TABLE
NORTH OF A TULSA TO FAYETTEVILLE LINE TONIGHT.
THUNDERSTORM PROBABILITY...50
SEVERE PROBABILITY IF STORMS OCCUR...40
SIGNIFICANT SEVERE PROBABILITY IF STORMS OCCUR...20

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

ADDITIONAL WEATHER INFORMATION...INCLUDING RELATED GRAPHICS CAN BE
FOUND AT: WWW.SRH.NOAA.GOV/TULSA.