Flash Flooding and Hail in Oklahoma, June 4, 2002

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
1100 AM CDT TUE JUN 4 2002

SHOWERS AND TSTMS CONTG TO DVLP ALG AND BEHIND FNT/OUTFLO ACRS NWRN
PORTIONS OF THE FA THIS MRNG. CURRENT FCST IS PRETTY WELL ON TARGET
AND WILL JUST NEED TO ADJUST FCST FOR POSITION OF THE SFC BNDRY.
HIGH POPS STILL LOOK WARRANTED AS SFC BOUNDARY CONTS TO PUSH SWD
INTO THE FA AND BROAD AREA OF LIFT CONTS INTO ADVANCE OF UPR SYS
MOVING OUT SRN NM.

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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
420 AM CDT TUE JUN 4 2002

COLD FRONT IS JUST NORTHWEST OF THE AREA THIS MORNING AND WILL BE
MAKING A PUSH INTO OKLAHOMA TODAY.  DIFFLUENT FLOW ALOFT INDICATES
BROAD AREA OF LIFT DEVELOPING TODAY WITH ENHANCED LIFT NEAR THE
FRONT.  WITH THIS BROAD UPWARD MOTION TODAY... WILL LIKELY BE
COOLING THE CAP LEVEL TEMPERATURES TODAY.  THUS PRECIP CHANCES
INCREASE BEGINNING THIS AFTERNOON.  THERE IS ALREADY HIGH BASED
CONVECTION THAT HAS DEVELOPED IN NORTH CENTRAL OKLAHOMA THIS
MORNING... AND AN AREA OF THUNDERSTORMS MOVING INTO NORTHWEST
OKLAHOMA FROM SOUTHWEST KANSAS AND THE OKLAHOMA PANHANDLE.  WILL GO
LIKELY POPS IN NORTH CENTRAL OKLAHOMA THIS AFTERNOON IN VICINITY OF
THE FRONT THIS AFTERNOON.  LIKELY POPS ARE SPREAD ACROSS THE AREA AS
THE FRONT PUSHES FARTHER SOUTH.  EASTERLY UPSLOP FLOW MAY HELP
DEVELOP A CONVECTIVE COMPLEX WEST TONIGHT THAT WILL MOVE THROUGH
PORTIONS OF THE AREA.  POPS DECREASE BEGINNING IN THE NORTHWEST
TOMORROW.

AVN STILL WANTS TO BRING A LOT COOLER AIR INTO THE AREA THAN THE
OTHER MODELS.  AVN 850 MB TEMPS ARE ABOUT 5C COOLER THAN OTHER
MODELS IN NORTHWEST OKLAHOMA BY LATE TOMORROW AFTERNOON AND THE MAV
GUIDANCE MAX IS ALSO SIGNIFICANTLY LOWER AT GAGE.  AT THE MOMENT I
STILL THINK THE AVN IS TOO COOL... SO HAVE GONE CLOSER TO WARMER FWC
AND ETA MOS NUMBERS TOMORROW IN AREAS WHERE SUN WILL POKE THROUGH
LATE... AND IN THE MID RANGE OF MOS GUIDANCE ELSEWHERE.

...SPEG.
OKC   85  64  76  58 /  40  70  60  20
HBR   86  64  75  56 /  40  70  60  10
SPS   89  66  79  59 /  30  70  60  20
GAG   81  57  76  51 /  50  70  40  10
PNC   85  61  75  55 /  60  70  50  10
DUA   89  68  76  59 /  20  60  70  30

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

OKZ004>048-050>052-TXZ083>090-042100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORMAN OK
1200 PM CDT TUE JUN 4 2002

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

LOCATION...
MAINLY NORTHWEST OF A LINE FROM HENRIETTA TEXAS TO SEMINOLE OKLAHOMA.

TIMING...THIS AFTERNOON THROUGH TONIGHT.

IMPACTS...
HAIL TO 1.5 INCHES IN DIAMETER MAY DAMAGE AUTOMOBILES...AND WIND
GUSTS TO 65 MPH MAY CAUSE STRUCTURAL DAMAGE TO PERSONAL PROPERTY AND
TREES.

RECOMMENDED ACTIONS...
EMERGENCY MANAGERS AND STORM SPOTTER GROUPS SHOULD BE PREPARED FOR
POSSIBLE ACTIVATION.

DISCUSSION...
A COLD FRONT OVER NORTHERN OKLAHOMA AT MIDDAY WILL CONTINUE TO PUSH
STEADILY SOUTHWARD THROUGH TONIGHT. THUNDERSTORMS WHICH DEVELOPED
ALONG AND NORTH OF THE BOUNDARY THIS MORNING WILL BECOME MORE
WIDESPREAD THIS AFTERNOON AND TONIGHT AS AN UPPER LEVEL STORM SYSTEM
MOVES NORTHEASTWARD FROM SOUTHERN NEW MEXICO. A FEW THUNDERSTORMS
MAY BECOME SEVERE THIS AFTERNOON WITH LARGE HAIL BEING THE MAIN
WEATHER THREAT. HOWEVER...EXTENSIVE CLOUD COVER AHEAD OF THE APPROACHING
UPPER SYSTEM WILL LIMIT INSTABILITY AND VERTICAL WIND SHEAR WILL
REMAIN RELATIVELY WEAK. THUS WIDESPREAD SEVERE WEATHER IS NOT
EXPECTED.

PROBABILITY TABLE...
VALID THROUGH 700 AM CDT WED JUN 5.
PROBABILITY OF THUNDERSTORMS OCCURRING IN THE
              NWS NORMAN COUNTY WARNING AREA...100 PERCENT.
PROBABILITY OF SEVERE STORMS IF STORMS OCCUR... 40 PERCENT.

OTHER HAZARDOUS WEATHER...
THE LARGE NUMBER OF THUNDERSTORMS EXPECTED TO DEVELOP OVER PARTS OF
THE AREA THIS AFTERNOON AND TONIGHT...COMBINED WITH SLOW
MOVEMENT...WILL LIKELY RESULT IN AREAS OF LOCALLY HEAVY RAIN. THE
RAIN COULD CONTINUE INTO WEDNESDAY...ESPECIALLY ACROSS SOUTHERN
OKLAHOMA...AND WESTERN NORTH TEXAS. SOME AREAS COULD RECEIVE SEVERAL
INCHES OF RAIN THROUGH WEDNESDAY.

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