Severe Thunderstorm Warning 157, NWS Tulsa, OK

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
330 AM CDT THU JUN 12 1997

LINE OF TSRA CONTINUING TO PROGRESS TOWARDS NRN COUNTIES. EVOLUTION
OF STORM SCALE FEATURES OVER THE NEXT FEW HOURS WILL BE INTERESTING
AS LEADING EDGE OF MCS MERGES WITH PERSISTENT BAND OF ELEVATED TSRA
WHICH INITIATED ON LLJ JUST NORTH OF THE KANSAS BORDER. RADAR HAS
ALREADY ESTIMATED VERY HEAVY RAINFALL IN THESE COUNTIES...NRLY 3"
IN THE LAST 2 HRS. MCS SHOULD CONTINUE INTO NE OK THIS MORNING
BEFORE WEAKENING AFTER LLJ DECREASES. COULD SEE HEAVY RAINFALL OVER
NRN COUNTIES BEFORE MCS WEAKENS. WL LIKELY ISSUE FFA OVER FAR NRN
COUNTIES AS FFG IS FAIRLY LOW ALONG THE KS BORDER. WILL USE
CATEGORICAL WORDING FOR PRECIP OVER NE OK ZONES THIS MORNING
BECOMING PARTLY CLOUDY BY AFT. WILL ALSO LEAVE IN LIKELY POPS FOR
NW AR BUT KEEP ONLY SLT CHC FOR SE OK. EXPECT BULK OF PRECIP TO BE
GONE BY EARLY AFT.

WITH STG WLY COMPONENT JUST OFF THE SFC TODAY...MODELS REALLY
WARMING UP H8-H9 LAYER. LOCAL GUIDANCE USING ETA AND NGM MODEL
GRIDS SUGGESTS HI TEMPS IN THE MID-UPPER 90S IF WE GET FULL
SUNSHINE. DONT EXPECT TEMPS THAT WARM WITH CLOUDS AND PRECIP IN NE
HALF...COULD GET CLOSE IN SW HALF THOUGH.

HARD TO SAY WHERE ANY OUTFLOW BOUNDARIES WILL SET UP LATE THIS AFT
AND TONIGHT. REGARDLESS...WITH COLD FRONT APRCHG CENTRAL OK AND ERN
KS THIS AFT...WILL LIKELY SEE A REPEAT TONIGHT. STORMS SHOULD FIRE
IN THE AFT ALONG FRONT MUCH CLOSER THAN THEY DID WED. LLJ SHOULD BE
ABOUT AS STRONG AS IT WAS THIS MORNING. HAVE GONE ABOVE GUIDANCE
FOR POPS IN NE OK COUNTIES FOR TONIGHT.

DONT WANT TO JUMP TOO FAR AHEAD IN THE FOCUS OF THIS FCST BUT
MODELS INDICATING STRONGER MID-LEVEL FLOW BY FRI WITH SFC LOW/FRONT
...DEPENDING ON WHICH MODEL YOU BELIEVE...SOMEWHERE IN CWA. WILL
LIKELY SEE MORE STORMS FRI AFT.

EXTENDED MODELS INDICATING CHC/GOOD CHC OF TSRA THROUGH THE WEEKEND
AS POS TILTED UPR TROUGH LIFTS OUT OVER THE SRN/CNTRL PLAINS.

TUL ET 090/068 089/067 089 4542
FSM ET 090/067 090/066 090 4333
MLC BT 093/070 092/068 091 2342
BVO BT 090/067 089/064 089 +742
FYV WE 087/067 089/064 085 7432
IDB BB 093/068 095/067 092 1223
BYV WT 086/066 086/063 083 7332

.TUL...
OK...FLASH FLOOD WATCH ZONES 55>58...61>63.
AR...NONE.

ARZ001-002-010-011-019-029-OKZ054>076-131200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
600 AM CDT THU JUN 12 1997

ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS EASTERN OKLAHOMA
AND NORTHWEST ARKANSAS TODAY AND TONIGHT.

AN LINE OF STRONG TO SEVERE THUNDERSTORMS WILL CONTINUE TO MOVE
SOUTHEASTWARD OVER EAST CENTRAL OKLAHOMA AND NORTHWEST ARKANSAS
EARLY THIS MORNING.  THESE THUNDERSTORMS SHOULD GENERALLY REMAIN
BELOW SEVERE LIMITS BEFORE EXITING THE AREA BY MID-MORNING.
HOWEVER...A FEW OF THESE STORMS MAY APPROACH SEVERE LIMITS ON
OCCASION.

AN OUTFLOW BOUNDARY ASSOCIATED WITH THIS MORNINGS STORMS WILL
PROVIDE A FOCUS FOR THUNDERSTORM DEVELOP THIS AFTERNOON.  THERE IS
SOME UNCERTAINTY IN THE EXACT LOCATION OF THIS BOUNDARY BY LATE
AFTERNOON...BUT IT WILL MOST LIKELY EXTEND ACROSS EAST CENTRAL OR
SOUTHEAST OKLAHOMA.  WITH HIGH TEMPERATURES EXPECTED TO REACH THE
LOWER 90S IN THAT AREA AND PLENTIFUL LOW-LEVEL MOISTURE ALREADY IN
PLACE... ANY STORMS THAT FORM WILL QUICKLY BECOME SEVERE.  THE MAIN
THREAT WITH THESE STORMS WILL BE LARGE HAIL AND DAMAGING WINDS...
BUT THE POSSIBILITY OF TORNADOES CANNOT BE RULED OUT.

THE MAIN LIMITING FACTOR FOR SEVERE THUNDERSTORM DEVELOPMENT TODAY
AND TONIGHT WILL BE THE LOCATION OF THE OUTFLOW BOUNDARY.  IF THE
BOUNDARY SLIPS JUST SOUTH OF THE AREA...THE PROBABILITY OF SEVERE
STORMS WILL BE SLIM.

EMERGENCY MANAGEMENT AGENCIES AND STORM SPOTTER GROUPS ACROSS
EASTERN OKLAHOMA AND NORTHWEST ARKANSAS SHOULD MONITOR THIS
DEVELOPING WEATHER SITUATION...AND BE READY FOR POSSIBLE ACTIVATION
LATER TODAY AND TONIGHT.