Severe Thunderstorm Warning 22, NWS Norman, OK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
310 PM CST MON FEB 11 2008

.DISCUSSION...
COUPLE OF BOUNDARIES IN NEAR THE FA...WITH PORTIONS OF THE
BOUNDARIES IN PARTS OF SOUTH CENTRAL AND SOUTHEAST OK. TEMPS RANGE
ACROSS THE CWA THIS AFTN WITH TEMPS AROUND 32 DEGREES IN NORTH
CENTRAL OK TO AROUND 70 IN SOUTH CENTRAL OK. BOUNDARIES WILL REMAIN
IN/NEAR THE AREA UNTIL A COLD FRONT BRINGING COOLER AIR MOVES ACROSS
THE AREA TONIGHT AS SHORTWAVE MOVES ACROSS THE CENTRAL U.S. SHOWERS
AND THUNDERSTORMS WILL BE POSSIBLE THIS EVENING... WITH THE BEST
CHANCE OF THUNDERSTORMS IN SOUTHEAST AND SOUTH CENTRAL OK NEAR THE
BOUNDARIES. ENOUGH INSTABILITY AND SHEAR MAY DEVELOP FOR SOME SEVERE
STORMS TO DEVELOP NEAR THE BOUNDARIES. RAIN WILL END FROM NORTH TO
SOUTH TONIGHT. RAIN MAY CHANGE TO FREEZING RAIN ACROSS PARTS OF
NORTH CENTRAL AND CENTRAL OKLAHOMA BEFORE ENDING AS COLDER AIR MOVES
INTO THE REGION. WINDS WILL SHIFT BACK TO THE SOUTH BY WEDNESDAY AND
BECOME BREEZY. THE BREEZY CONDITIONS... WARM TEMPS AND DRY AIR IN
WESTERN PORTIONS OF THE FA WILL INCREASE FIRE WX CONCERNS FOR WED
AFTN.

FOCUS THEN SHIFTS TO POTENTIAL WINTER WX/STORM LATE THIS WEEK INTO
THE WEEKEND. MODELS DIFFER BETWEEN EACH OTHER AND FROM RUN TO RUN ON
TIMING AND PATH OF SYSTEM... BUT AGREE THAT A STRONG COLD FRONT
BRINGING ARCTIC AIR WILL MOVE ACROSS THE FA THU. MEANWHILE... UPR
SYSTEM WILL MOVE SOUTHEAST FROM PACIFIC NORTHWEST WITH A CLOSED LOW
DEVELOPING IN THE FOUR CORNERS REGION BY LATE THU. PAST THIS POINT
IS WHERE MODELS BEGIN TO DIVERGE WITH ECMWF THE SLOWEST WITH THE UPR
SYSTEM. THE 12Z RUN OF THE GFS STARTED TO TREND TOWARDS THE SLOWER
SOLN BUT STILL IS DIFFERENT WITH THE PATH OF THE UPR SYSTEM FURTHER
NORTH. TRENDED TOWARDS THE SLOWER SOLN FOR THIS FORECAST PACKAGE.
WINTRY PRECIP WILL BE POSSIBLE LATE THIS WEEK INTO THE WEEKEND WITH
THE COLD AIR MOVING INTO PLACE OVER THE REGION BEFORE THIS UPR
SYSTEM BEGINS TO INFLUENCE THE AREA. DEPENDING ON TRACK AND TIMING
OF THE UPR SYSTEM... SOME SIGNIFICANT WINTER PRECIP MAY BE POSSIBLE
FOR PARTS OF THE FA. CURRENTLY HAVE PRECIP CHANCES ACROSS PORTIONS
OF THE AREA THURSDAY NIGHT INTO SATURDAY DUE TO UNCERTAINTIES...WITH
HIGHEST CHANCES ACROSS SOUTHERN PORTIONS OF FA. MODELS SHOW UPR
SYSTEM MOVING EAST OF THE AREA SUNDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  30  49  26  61 /  50  10   0   0
HOBART OK         31  51  28  65 /  30   0   0   0
WICHITA FALLS TX  37  53  30  67 /  60  10   0   0
GAGE OK           22  51  22  65 /  10   0   0   0
PONCA CITY OK     22  42  24  57 /  20  10   0   0
DURANT OK         39  50  27  59 /  80  20   0   0

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

24/25

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORMAN OK
1200 PM CST MON FEB 11 2008

OKZ004>048-050>052-TXZ083>090-121300-
HARPER-WOODS-ALFALFA-GRANT-KAY-ELLIS-WOODWARD-MAJOR-GARFIELD-NOBLE-
ROGER MILLS-DEWEY-CUSTER-BLAINE-KINGFISHER-LOGAN-PAYNE-BECKHAM-
WASHITA-CADDO-CANADIAN-OKLAHOMA-LINCOLN-GRADY-MCCLAIN-CLEVELAND-
POTTAWATOMIE-SEMINOLE-HUGHES-HARMON-GREER-KIOWA-JACKSON-TILLMAN-
COMANCHE-STEPHENS-GARVIN-MURRAY-PONTOTOC-COAL-COTTON-JEFFERSON-
CARTER-JOHNSTON-ATOKA-LOVE-MARSHALL-BRYAN-HARDEMAN-FOARD-WILBARGER-
WICHITA-KNOX-BAYLOR-ARCHER-CLAY-
1200 PM CST MON FEB 11 2008

THIS HAZARDOUS WEATHER OUTLOOK COVERS NORTHERN...WESTERN...
CENTRAL...AND SOUTHERN OKLAHOMA...AND WESTERN NORTH TEXAS.

.DAY ONE...THIS AFTERNOON AND TONIGHT...

THUNDERSTORM OUTLOOK...
THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TODAY AND TONIGHT
ACROSS PORTIONS OF SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS.

LOCATION...
THE SLIGHT RISK AREA IS SOUTHEAST OF A LINE FROM HENRIETTA TEXAS...
TO PAULS VALLEY... TO SEMINOLE.

TIMING...
THE MOST LIKELY TIME FOR SEVERE THUNDERSTORMS WILL BE BETWEEN 4 PM
AND MIDNIGHT.

IMPACTS...
GOLFBALL SIZE HAIL AND WINDS TO 65 MPH WILL BE THE PRIMARY HAZARDS.

RECOMMENDED ACTIONS...
STORM SPOTTER GROUPS AND EMERGENCY MANAGEMENT PERSONNEL ACROSS THE
RISK AREA SHOULD BE PREPARED FOR THE POSSIBILITY OF SEVERE
THUNDERSTORMS FROM 4 PM UNTIL 10 PM.

DISCUSSION...
A FRONTAL BOUNDARY ACROSS FAR NORTHERN TEXAS IS EXPECTED TO LIFT
NORTH TO NEAR THE NORTHERN EDGES OF THE SLIGHT RISK AREA BY LATE
THIS AFTERNOON. MEANWHILE...ANOTHER UPPER LEVEL DISTURBANCE WILL
APPROACH THE REGION...AND ASSIST IN ALLOWING A MODERATELY UNSTABLE
AIRMASS TO DEVELOP NEAR THE FRONT. BY LATE THIS AFTERNOON...LIFT MAY
BECOME SUFFICIENT TO INITIATE THUNDERSTORMS ALONG THE FRONTAL
BOUNDARY... WITH INSTABILITY AND SHEAR POSSIBLY SUFFICIENT FOR A FEW
ORGANIZED SEVERE THUNDERSTORMS. ISOLATED SUPERCELLS WILL BE
POSSIBLE... CAPABLE OF PRODUCING GOLFBALL SIZE HAIL AND WINDS TO 65
MPH OVER SOUTH CENTRAL AND SOUTHEASTERN OKLAHOMA.

BY EARLY THIS EVENING...LIFT IS EXPECTED TO INCREASE ALONG AND JUST
NORTH OF THE FRONTAL BOUNDARY...RESULTING IN MORE NUMEROUS
THUNDERSTORMS...WITH QUARTER SIZE HAIL THE PRIMARY HAZARD. THE
SEVERE WEATHER THREAT IS EXPECTED TO END LATE THIS EVENING... AS ANY
THUNDERSTORMS MOVE INTO NORTH CENTRAL AND NORTHEASTERN TEXAS.

PROBABILITY TABLE...
VALID THROUGH 700 AM CST TUESDAY FEB 12.
PROBABILITY OF THUNDERSTORMS OCCURRING IN THE
              NWS NORMAN COUNTY WARNING AREA...80 PERCENT.
PROBABILITY OF SEVERE STORMS IF STORMS OCCUR...40 PERCENT.

OTHER HAZARDOUS WEATHER...
THERE IS A LOW CHANCE THAT RAIN TONIGHT MAY MIX WITH OR CHANGE TO
FREEZING RAIN OR SLEET NEAR AND JUST SOUTH OF INTERSTATE 40 BEFORE
ENDING. HOWEVER...NO SIGNIFICANT ACCUMULATIONS OF ICE ARE EXPECTED.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY...

THUNDERSTORM OUTLOOK...
THUNDERSTORMS ARE NOT EXPECTED.

OTHER HAZARDOUS WEATHER...
MUCH WARMER...WINDY...AND DRY CONDITIONS SHOULD RETURN TO THE REGION
ON WEDNESDAY...WITH EXTREME WILDFIRE BEHAVIOR POSSIBLE TO THE WEST
OF INTERSTATE 35.

MORE WINTRY WEATHER...INCLUDING A CHANCE OF ICE AND SNOW...IS
EXPECTED TO AFFECT THE REGION THURSDAY NIGHT AND FRIDAY. ALTHOUGH
SOME UNCERTAINTY REMAINS AS TO THE DETAILS...IT APPEARS THAT A
STRONG COLD FRONT WILL MOVE ACROSS THE REGION ON THURSDAY...FOLLOWED
BY INCREASING CHANCES OF ICE OR SNOW... PARTICULARLY NEAR AND SOUTH
OF INTERSTATE 44. THERE IS ALSO A POSSIBILITY THAT THE STORM SYSTEM
WILL APPROACH SLOWER THAN EXPECTED... WHICH WOULD RESULT IN THE
CHANCES FOR WINTRY PRECIPITATION CONTINUING INTO SATURDAY.

THE NEXT SCHEDULED HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED AT 7 AM
TUESDAY.

24

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
737 PM CST MON FEB 11 2008

OKZ027-040-120145-
GRADY OK-GARVIN OK-
737 PM CST MON FEB 11 2008

...SIGNIFICANT WEATHER ADVISORY...

THIS SIGNIFICANT WEATHER ADVISORY IS FOR GARVIN AND GRADY COUNTIES.

A STRONG THUNDERSTORM WAS LOCATED OVER COX CITY AT 737 PM CST...
MOVING EAST AT 25 MPH.

SMALL HAIL IS POSSIBLE WITH THIS STORM.

PEOPLE IN GARVIN AND GRADY COUNTIES SHOULD MONITOR THE WEATHER
SITUATION CLOSELY. LISTEN FOR WARNINGS AND REMAIN ALERT FOR
THREATENING WEATHER CONDITIONS.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
759 PM CST MON FEB 11 2008

OKZ028-040-120215-
MCCLAIN OK-GARVIN OK-
759 PM CST MON FEB 11 2008

...SIGNIFICANT WEATHER ADVISORY...

THIS SIGNIFICANT WEATHER ADVISORY IS FOR GARVIN AND MCCLAIN COUNTIES.

A STRONG THUNDERSTORM WAS LOCATED 7 MILES SOUTHWEST OF MAYSVILLE AT
759 PM CST...MOVING NORTHEAST AT 35 MPH.

VERY HEAVY RAIN...SMALL HAIL AND FREQUENT LIGHTNING ARE LIKELY WITH
THIS STORM.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
835 PM CST MON FEB 11 2008

OKZ028-040-120300-
MCCLAIN OK-GARVIN OK-
835 PM CST MON FEB 11 2008

...SIGNIFICANT WEATHER ADVISORY...

THIS SIGNIFICANT WEATHER ADVISORY IS FOR GARVIN AND MCCLAIN COUNTIES.

A STRONG THUNDERSTORM WAS LOCATED 3 MILES EAST OF WHITEBEAD AT 835 PM
CST...MOVING EAST AT 30 MPH.

HEAVY RAIN...FREQUENT LIGHTNING AND SMALL HAIL ARE LIKELY WITH THIS
STORM.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
857 PM CST MON FEB 11 2008

OKZ028-040-042-120315-
MCCLAIN OK-GARVIN OK-PONTOTOC OK-
857 PM CST MON FEB 11 2008

...SIGNIFICANT WEATHER ADVISORY...

THIS SIGNIFICANT WEATHER ADVISORY IS FOR GARVIN...MCCLAIN AND
PONTOTOC COUNTIES.

A STRONG THUNDERSTORM WAS LOCATED 4 MILES SOUTH OF BYARS AT 857 PM
CST...MOVING EAST AT 30 MPH.

HEAVY RAIN...FREQUENT LIGHTNING AND SMALL HAIL CAN BE EXPECTED AS
THE STORM MOVES THROUGH THE BYARS AND STRATFORD AREAS.