SPC AC 090602
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0102 AM CDT FRI APR 09 2004
VALID 091200Z - 101200Z
THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 60 NW
AUS 35 SSE GGG 20 SSW ELD 20 WNW LIT 35 SSW HRO 30 NE MKO 40 S PNC
20 NNE GAG 40 SW GAG 40 N CDS 40 SSW LTS 55 N ABI 35 NNE SJT 40 NNE
JCT 60 NW AUS.
GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 ESE P07 50 NNE P07
MAF 30 SW HOB 30 WNW CNM 20 ESE DMN 30 NNE DUG 50 WNW GBN 10 SSW TRM
15 SSE EDW 30 NNW NID 45 S P38 25 SSE MLF 40 E DPG 30 E BYI 30 NW
SUN 45 SSW S80 45 ESE 63S 80 ENE 63S 45 N FCA 50 SSE BIL 30 WSW DGW
15 NNE CYS 30 S AKO 35 NNW GCK 25 SW HUT 15 E SGF 10 ESE PAH 35 SW
CKV 25 NW MSL 25 SW CBM 45 NNE HEZ 25 WNW POE 40 WSW GLS.
GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 60 W MIA 10 NNW VRB.
...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF TX/OK INTO WRN
AR...
...SYNOPSIS...
THE SHORTWAVE TROUGH NOW OVER NM WILL DE-AMPLIFY AND WEAKEN AS IT
MOVES EWD THROUGH OK EARLY IN THE PERIOD AND INTO THE MS VALLEY THIS
EVENING. A SECONDARY WEAKER SHORTWAVE NOW OVER CNTRL CA WILL WEAKEN
AND SHEAR EWD INTO THE SRN PLAINS FRIDAY NIGHT. COLD FRONT OVER THE
NRN PLAINS WILL DEVELOP SWD INTO OK AND THE TX PANHANDLE BY EVENING.
WEAK SURFACE FRONT CURRENTLY EXTENDS FROM THE SERN STATES WWD
THROUGH NRN TX...WHERE IT INTERSECTS AN OUTFLOW BOUNDARY ASSOCIATED
WITH ONGOING CONVECTION OVER W TX. CURRENT THINKING IS THAT
PRECIPITATION WILL SPREAD EWD ALONG AND N OF THIS FRONT INTO
WRN/CNTRL OK AND EXTREME NRN TX AS LOW LEVEL JET VEERS AND
ASSOCIATED WARM ADVECTION ZONE SHIFTS EWD.
...OK/TX AREAS...
THE FRONT NEAR THE RED RIVER MAY BE REINFORCED BY PRECIPITATION
ASSOCIATED WITH MCS AS IT CONTINUES MAINLY THROUGH OK EARLY FRIDAY.
THOUGH CLOUDS AND RAIN COOLED AIR MAY IMPEDE NWD PROGRESS OF THE
BOUNDARY...IT SHOULD BEGIN TO LIFT NWD INTO AT LEAST SRN OK DURING
THE DAY AS WARM ADVECTION PRECIPITATION SHIFTS EWD. MODEST LOW LEVEL
MOISTURE CURRENTLY RESIDES OVER MUCH OF TX WITH DEWPOINTS GENERALLY
IN THE MID TO UPPER 50S. THIS MOISTURE WILL ADVECT NWD THROUGH TX
AND INTO PARTS OF SRN/CNTRL OK DURING THE DAY UNDERNEATH STEEPENING
LAPSE RATES WITH MLCAPE FROM 1500 TO 2000 J/KG POSSIBLE.
THE SHORTWAVE TROUGH WILL MOVE EAST OF THE AREA EARLY IN THE
PERIOD...AND AS THIS OCCURS THE LOW LEVEL FLOW WILL VEER AND WEAKEN
DURING THE DAY. MID LEVEL SUBSIDENCE AND WEAKENING/VEERING LOW LEVEL
FLOW MAY POSE A LIMITING FACTOR...ESPECIALLY WITH REGARD TO
INITIATION ALONG THE DRYLINE THAT IS EXPECTED TO DEVELOP FROM WRN OK
THROUGH THE ERN PART OF W TX. THOUGH ISOLATED STORMS MAY STILL BE
POSSIBLE ALONG THE DRYLINE GIVEN WEAK CAP...THERE IS A HIGHER
CONFIDENCE THAT STORMS WILL REDEVELOP/INTENSIFY FARTHER NE IN WARM
ADVECTION ZONE FROM N TX INTO SRN/CNTRL OK. FRONTOGENETIC FORCING
WILL INCREASE ACROSS OK DURING THE EVENING AS SURFACE HIGH PRESSURE
BUILDS SWD. THE SHARPENING BOUNDARY AND INCREASING SLY LOW LEVEL JET
OVERNIGHT WILL ENHANCE LIFT AND SUPPORT CONTINUED DEVELOPMENT OF
STORMS...POSSIBLY EVOLVING INTO AN MCS FROM SERN OK INTO THE LOWER
MS VALLEY AREA.
THOUGH LOW LEVEL FLOW IS EXPECTED TO REMAIN VEERED...SHEAR THROUGH A
DEEPER LAYER WILL REMAIN SUFFICIENT TO SUPPORT A THREAT OF ISOLATED
SUPERCELLS WITH ANY STORMS DEVELOPING ALONG THE DRYLINE OR IN WARM
ADVECTION ZONE FARTHER E. LARGE HAIL WILL BE THE MAIN
THREAT...THOUGH ISOLATED DAMAGING WIND WILL ALSO BE POSSIBLE...
ESPECIALLY FROM SE OK/NE TX INTO WRN AR AS ACTIVITY EVOLVES INTO AN
MCS. THOUGH LOW LEVEL SHEAR WILL NOT BE PARTICULARLY STRONG...
AN ISOLATED TORNADO OR TWO MAY BE POSSIBLE...MAINLY WITH ANY STORM
DEVELOPING ON OR INTERACTING WITH E-W BOUNDARY THAT MAY PERSIST
ACROSS SRN OR CNTRL OK.
..DIAL/TAYLOR.. 04/09/2004
...NOTICE...
FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3. THE
INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED FOR 1300Z
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