Severe Thunderstorm Warning 337, NWS Norman, OK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OKLAHOMA
318 AM CDT WED MAY 14 2003

CONVECTION CONTINUES TO DEVELOP OVER THE AREA AND SHOULD CONTINUE
THRU THE MORNING HOURS UNTIL THE LL JET WEAKENS AND CONVECTION MOVES
OFF TO THE EAST. WILL CONTINUE TO MONITOR RADAR AND MAKE ANY NEEDED
LAST MINUTE CHANGES TO POPS. LL MOISTURE CONTINUES TO INCREASE
ACROSS THE FA... WITH LOW 70 DEWPTS IN PORTIONS OF CENTRAL AND
SOUTHERN OK. SEVERAL BOUNDARIES WILL ONCE AGAIN BE NEAR OR IN THE
AREA TODAY. A COLD FRONT CONTINUES TO MOVE SOUTHWARD ACROSS KANSAS
AND IS EXPECTED TO STALL IN SOUTHERN KS/NORTHERN OK LATER TODAY.
OUTFLOW BOUNDARIES FROM THIS MORNINGS CONVECTION ARE EXPECTED TO BE
IN THE AREA. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO REDEVELOP
ALONG THESE BOUNDARIES LATER THIS AFTN INTO TONIGHT. SOME OF THESE
STORMS COULD BECOME SEVERE WITH LARGE HAIL AND DAMAGING WINDS THE
PRIMARY THREAT.

SHOWERS AND THUNDERSTORMS WILL CONTINUE TO BE POSSIBLE THURS THRU
FRI ACROSS THE AREA AS THE UPR LVL TROUGH CURRENTLY OFF THE WEST
COAST OF CALIFORNIA APPROACHES AND MOVES ACROSS THE SOUTHERN PLAINS.
THE WEEKEND SHOULD REMAIN DRY AFTER THIS UPR LVL STORM SYSTEM MOVES
OFF TO THE EAST. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL
RETURN EARLY NEXT WEEK TO THE FA.

PRELIMINARY NUMBERS...
OKC   82   63   80   61  /100   20   30   50
HBR   85   62   80   61  / 50   20   30   50
SPS   87   66   85   65  / 80   30   30   50
GAG   83   58   77   58  / 40   20   30   50
PNC   80   59   77   58  / 40   20   20   50
DUA   84   66   84   65  /100   30   30   50

FORECAST ID = 25

.OUN...
OK...NONE.
TX...NONE.

OKZ004>048-050>052-TXZ083>090-141200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORMAN OK
1200 PM CDT TUE MAY 13 2003

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

.DAY ONE...TODAY AND TONIGHT...

THUNDERSTORM OUTLOOK...
THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THROUGH TONIGHT
ACROSS MUCH OF OKLAHOMA AND WESTERN NORTH TEXAS.

LOCATION...
THE SLIGHT RISK INCLUDES ALL OF WESTERN...CENTRAL...AND SOUTHEAST
OKLAHOMA AND WESTERN NORTH TEXAS.

TIMING...
THE MOST LIKELY TIME FOR SEVERE THUNDERSTORMS WILL BE FROM LATE
AFTERNOON THROUGH TONIGHT.

RECOMMENDED ACTIONS...
STORM SPOTTER GROUPS AND EMERGENCY MANAGEMENT PERSONNEL ACROSS THE
RISK AREA SHOULD PLAN FOR SEVERE WEATHER OPERATIONS FROM LATE
AFTERNOON THROUGH THE NIGHT.

DISCUSSION...
A SURFACE LOW PRESSURE CENTER WILL CONTINUE TO DEVELOP OVER
SOUTHWEST KANSAS AND MOVE SLOWLY EAST THROUGH THE AFTERNOON. THE
DRYLINE SOUTH OF THIS LOW IS EXPECTED TO MOVE AS FAR EAST AS THE
MAIN BODY OF NORTHWEST OKLAHOMA AFTER MID-AFTERNOON AND RANGE SOUTH
INTO THE SOUTHERN TEXAS PANHANDLE. A WEAK WARM FRONT ACROSS CENTRAL TEXAS
THAT THIS MORNING HAD LOWER 70 DEWPOINTS SOUTH OF IT WILL MOVE INTO
SOUTHERN OKLAHOMA BY EARLY EVENING. THIS WILL PROVIDE INCREASINGLY
FAVORABLE CONDITIONS NEAR THE SURFACE.

ALTHOUGH BOUNDARY LAYER MOISTURE WILL CONTINUE TO INCREASE RAPIDLY
OVER MOST OF THE RISK AREA BOOSTING CAPE VALUES...STRONG WARM AIR
ADVECTION ABOVE THE MOIST LAYER WILL SERVE AS AN INHIBITOR TO STORM
DEVELOPMENT. HOWEVER...STRONG SURFACE HEATING ACROSS THE SOUTHERN
TEXAS PANHANDLE AND WESTERN NORTH TEXAS MAY HELP TO START STORMS
ALONG THE DRYLINE.

SHEAR PROFILES SHOULD BE SUFFICIENT FOR THE DEVELOPMENT OF SUPERCELL
STORMS IF STRONG SURFACE HEATING CAN OVERCOME THE CAPPING THERMAL
INVERSION THAT WILL BE INCREASING OVER THE AREA THROUGH THE DAY.

A SECONDARY FEATURE FOR DEVELOPMENT MAY BE AN OLD OUTFLOW BOUNDARY
ACROSS NORTHEAST OKLAHOMA FROM MORNING STORMS IN SOUTHEAST KANSAS.

AFTER MIDNIGHT A COLD FRONT IS EXPECTED TO MOVE INTO NORTHWEST
OKLAHOMA. THIS BOUNDARY WILL PROVIDE YET ANOTHER FOCUS FOR STORM
DEVELOPMENT OVERNIGHT. NORTH CENTRAL AND CENTRAL OKLAHOMA ARE AREAS
MOST LIKELY TO HAVE STORMS OVERNIGHT AS THE FRONT MOVES SOUTHEAST
INTO AN AREA OF DEEPER MOISTURE AND MORE FAVORABLE BOUNDARY LAYER
WINDS. THESE STORMS MAY ORGANIZE INTO A MESOSCALE CONVECTIVE SYSTEM
LATER TONIGHT AND EARLY WEDNESDAY.

THE MAIN THREATS FROM LATE AFTERNOON AND EVENING STORMS WOULD BE
LARGE HAIL AND STRONG WINDS. ALTHOUGH THE TORNADO THREAT IS NON-
ZERO...IT IS EXPECTED TO BE LOW. THE MAIN OVERNIGHT THREATS ARE
EXPECTED TO BE STRONG WINDS AND LARGE HAIL.

PROBABILITY TABLE...
VALID THROUGH 700 AM CDT WEDNESDAY MAY 14.
PROBABILITY OF THUNDERSTORMS OCCURRING IN THE
              NWS NORMAN COUNTY WARNING AREA...60 PERCENT.
PROBABILITY OF SEVERE STORMS IF STORMS OCCUR...80 PERCENT.

OTHER HAZARDOUS WEATHER...
NONE.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY...

THUNDERSTORM OUTLOOK...
THUNDERSTORMS WILL BE POSSIBLE FROM WEDNESDAY THROUGH LATE FRIDAY.
THE GREATEST RISK OF SEVERE WEATHER WILL BE ON WEDNESDAY AND
THURSDAY.

OTHER HAZARDOUS WEATHER...
NONE

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

WR

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
152 AM CDT WED MAY 14 2003

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

0148 AM    2 W CYRIL                 OK   .75 INCH HAIL
05/14/03   CADDO

SC

OKZ028-040-140730-

SIGNIFICANT WEATHER ADVISORY
NATIONAL WEATHER SERVICE NORMAN OK
218 AM CDT WED MAY 14 2003

THIS SIGNIFICANT WEATHER ADVISORY IS FOR GARVIN AND MCCLAIN COUNTIES.

A SEVERE THUNDERSTORM WAS LOCATED 15 MILES WEST OF LINDSAY AT 218 AM
CDT...MOVING EAST AT 30 MPH.

PEOPLE IN GARVIN AND MCCLAIN COUNTIES SHOULD MONITOR THIS STORM
CLOSELY. LISTEN FOR WARNINGS AND WATCH FOR THREATENING WEATHER
CONDITIONS AS THIS STORM APPROACHES.

30

OKZ028-040-041-046-140815-

SIGNIFICANT WEATHER ADVISORY
NATIONAL WEATHER SERVICE NORMAN OK
246 AM CDT WED MAY 14 2003

THIS SIGNIFICANT WEATHER ADVISORY IS FOR CARTER...GARVIN...MCCLAIN
AND MURRAY COUNTIES.

A LINE OF SEVERE THUNDERSTORMS WAS LOCATED FROM 22 MILES WEST OF COLE
TO 9 MILES WEST OF RATLIFF CITY AT 246 AM CDT...MOVING EAST AT 20
MPH. HAIL TO THE SIZE OF BASEBALLS AND WIND GUSTS TO 65 MPH WILL BE
POSSIBLE WITH THESE SEVERE THUNDERSTORMS.

PEOPLE IN CARTER...GARVIN...MCCLAIN AND MURRAY COUNTIES SHOULD
MONITOR THIS STORM CLOSELY. LISTEN FOR WARNINGS AND WATCH FOR
THREATENING WEATHER CONDITIONS AS THIS STORM APPROACHES.

30

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
347 AM CDT WED MAY 14 2003

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

0148 AM    2 W CYRIL                 OK   .75 INCH HAIL
05/14/03   CADDO                          REPORTED BY SPOTTER.

0155 AM    2 W CYRIL                 OK   .88 INCH HAIL
05/14/03   CADDO                          REPORTED BY SPOTTER.

0158 AM    2 W CYRIL                 OK   1.50 INCH HAIL
05/14/03   CADDO                          REPORTED BY SPOTTER.

0328 AM    VICI                      OK   .88 INCH HAIL
05/14/03   DEWEY                          REPORTED BY SPOTTER

0350 AM    2 E GRAHAM                OK   1.00 INCH HAIL
05/14/03   CARTER                         REPORTED BY SPOTTER THROUGH
                                          MURRAY CO. EMERGENCY
                                          MANAGER.

TY/SC/CJS

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
358 AM CDT WED MAY 14 2003

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

0338 AM    2 S LINDSAY               OK   .88 INCH HAIL
05/14/03   GARVIN                         REPORTED BY SPOTTER.

0400 AM    1 W ARDMORE               OK   1.00 INCH HAIL
05/14/03   CARTER                         REPORTED BY SPOTTER
                                          THROUGH MURRAY CO.
                                          EMERGENCY MANAGER.

TY

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
408 AM CDT WED MAY 14 2003

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

0407 AM    ARDMORE                   OK   1.75 INCH HAIL
05/14/03   CARTER                         REPORTED BY ARDMORE
                                          EMERGENCY MANAGER.

TY/DA