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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 310

NWS STORM PREDICTION CENTER NORMAN OK

350 PM CDT MON MAY 28 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHWEST OKLAHOMA

       NORTHWEST TEXAS



EFFECTIVE THIS MONDAY AFTERNOON FROM 350 PM UNTIL MIDNIGHT CDT.



HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 60

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 40 MILES WEST OF BIG

SPRING TEXAS TO 45 MILES EAST SOUTHEAST OF FORT SILL OKLAHOMA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU0).



REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE

FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH

AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR

THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS

AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY

DO PRODUCE TORNADOES.



OTHER WATCH INFORMATION...CONTINUE...WW 308...WW 309...



DISCUSSION...THE LATEST SFC ANALYSIS SHOWS A DIFFUSE FRONTAL

BOUNDARY FROM NEAR CHILDRESS EXTENDING SWWD INTO FAR SE NM. TO THE

SOUTHEAST OF THE BOUNDARY...MODERATE TO STRONG INSTABILITY IS IN

PLACE WITH MLCAPE ESTIMATED IN THE 2000 TO 3000 J/KG RANGE. THE

CAPPING INVERSION IS NOW GONE AND A FIELD OF CUMULUS IS GROWING ON

THE NWRN EDGE OF INSTABILITY IMMEDIATELY SOUTHEAST OF THE FRONT.

SHORT-TERM MODEL FORECASTS ARE IN FAIRLY GOOD AGREEMENT...INITIATING

STORMS IN THE 2030Z TO 2130Z TIMEFRAME BETWEEN MIDLAND AND LUBBOCK

WITH CONVECTION EXPANDING NEWD INTO THE LOW ROLLING PLAINS OF NW TX

AND INTO SW OK. THE LATEST WSR-88D VWPS WCNTRL TX SHOW 30 TO 40 KT

OF DEEP LAYER SHEAR WHICH COMBINED WITH LAPSE RATES AROUND 8.0 C/KM

SHOULD BE FAVORABLE FOR SUPERCELLS WITH LARGE HAIL. DEEP LAYER SHEAR

IS FORECAST TO INCREASE TOWARD EARLY EVENING AS THE LOW-LEVEL JET

STRENGTHENS. THIS ALONG WITH THE PRISTINE THERMODYNAMIC ENVIRONMENT

MAY ENABLE THE MORE DOMINANT SUPERCELLS TO HAVE HAIL GREATER THAN 2

INCHES IN DIAMETER. AN ISOLATED WIND DAMAGE THREAT SHOULD ALSO

DEVELOP AS THE CELLS MATURE.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 26025.





...CARBIN/BROYLES

