Severe weather forecast for Aril, 09, 2012

..THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON THROUGH TONIGHT
FOR WRN OK AND NW TX...

...WRN OK/NW TX AREA THROUGH TONIGHT...
A DIFFUSE FRONT EXTENDS FROM NRN OK INTO SW KS...WITH BOUNDARY LAYER
DEWPOINTS OF 56-60 F REPRESENTATIVE OF THE TX/OK WARM SECTOR N OF
I-10. ALOFT...THE LARGE SCALE RIDGE EXTENDS FROM FAR W TX NNWWD TO
THE NRN ROCKIES...THOUGH AN EMBEDDED/SUBTLE SPEED MAX IS EXPECTED TO
CREST THE RIDGE IN CO TODAY AND MOVE SEWD OVER OK TONIGHT. DAYTIME
HEATING/MIXING WILL HELP CONSOLIDATE A DRYLINE ACROSS THE
CENTRAL/ERN TX PANHANDLE THIS AFTERNOON. THE PRIMARY FOCUS FOR
THUNDERSTORM DEVELOPMENT WILL BE THE DRYLINE/FRONT IN ADVANCE OF THE
SUBTLE SPEED MAX THIS AFTERNOON...WITH STORMS EXPECTED TO SPREAD
SEWD ACROSS WRN/CENTRAL OK AND NW TX OVERNIGHT.

MODIFIED FORECAST AND OBSERVED SOUNDINGS SUPPORT AFTERNOON MLCAPE
VALUES NEAR 1500 J/KG AS A RESULT OF THE MODEST LOW-LEVEL MOISTURE
BENEATH MIDLEVEL LAPSE RATES OF 8.5 C/KM. MEANWHILE...VERTICAL
SHEAR PROFILES ARE FORECAST TO BE FAVORABLE FOR SSEWD-MOVING
SUPERCELLS WITH NWLY EFFECTIVE-BULK SHEAR OF 35-45 KT. LOW-LEVEL
SHEAR WILL BE STRONGEST INVOF THE SURFACE FRONT ACROSS NW OK THIS
AFTERNOON...WHERE EFFECTIVE SRH COULD APPROACH 200 M2/S2.

THE GENERAL SCENARIO IS FOR STORMS TO FORM AROUND 21Z NEAR THE
DRYLINE/FRONT INTERSECTION AND THEN SPREAD SEWD THROUGH THE EVENING.
DISCRETE SUPERCELLS WILL BE POSSIBLE WITH THE INITIAL
DEVELOPMENT...WITH AN ATTENDANT RISK FOR VERY LARGE HAIL AND A
COUPLE OF TORNADOES. LATER THIS EVENING INTO TONIGHT...CONVECTION
WILL TEND TO GROW UPSCALE INTO A CLUSTER OR TWO...AIDED BY A 30 KT
SSWLY LLJ AND ASSOCIATED WARM ADVECTION. THE RISK FOR AT LEAST
ISOLATED LARGE HAIL AND DAMAGING WINDS WILL PERSIST WELL INTO
TONIGHT.

...FAR W TX/SE NM THIS AFTERNOON/EVENING...
BOUNDARY LAYER DEWPOINTS IN THE 40S TO NEAR 50 HAVE SPREAD WWD INTO
FAR W TX/SE NM. THE 12Z EL PASO SOUNDING SUPPORTS THE POTENTIAL FOR
HIGH-BASED STORM DEVELOPMENT THIS AFTERNOON NEAR AND JUST E OF THE
HIGHER TERRAIN. MLCAPE APPROACHING 1000 J/KG AND EFFECTIVE BULK
SHEAR NEAR 25 KT SUGGEST SOME RISK FOR ISOLATED HAIL/STRONG WIND
GUSTS.

..THOMPSON/ROGERS.. 04/09/2012