MESOSCALE DISCUSSION 2288
NWS STORM PREDICTION CENTER NORMAN OK
1227 PM CST MON NOV 07 2011

AREAS AFFECTED...NWRN TX/SERN TX PANHANDLE...SWRN OK

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 071827Z - 072000Z

PORTIONS OF NWRN TX/SERN TX PANHANDLE AND SWRN OK ARE BEING
MONITORED FOR THUNDERSTORM INITIATION AND INCREASING SVR WEATHER
THREAT. A TORNADO WATCH WILL LIKELY BE NEEDED DURING EARLY TO MID
AFTERNOON.

MIDDAY SURFACE ANALYSIS PLACES A WEAK AREA OF LOW PRESSURE OVER W
TX...WITH A QUASI-STATIONARY FRONT EXTENDING NEWD ACROSS WRN OK INTO
FAR SERN KS. VERY MOIST BOUNDARY LAYER AIRMASS CONTINUES TO ADVECT
N-NW INTO THE REGION...WITH SURFACE DEWPOINTS GENERALLY IN THE LOW
TO MID 60S. IN ADDITION...PARTIAL CLEARING OVER THE WARM SECTOR IS
ALLOWING TEMPERATURES TO WARM INTO THE UPR 60S TO LOW 70S. THOUGH
PRIMARY FORCING FOR ASCENT REMAINS WELL W OF THE SRN PLAINS...VIS
SATELLITE IMAGERY INDICATES AGITATED CUMULUS FIELD/CLOUD STREETS
WITH EMBEDDED TOWERING CUMULUS ARE DEEPENING OVER NWRN TX. THIS AREA
OF IMPLIED BOUNDARY LAYER DESTABILIZATION IS JUXTAPOSED WITH
MODERATE INSTABILITY /MLCAPE VALUES UP TO 1500 J PER KG/ AND AMPLE
DEEP LAYER VERTICAL WIND SHEAR FOR ORGANIZED THUNDERSTORM
DEVELOPMENT...INCLUDING SUPERCELLS. ANOTHER FACTOR FAVORING
SUPERCELL DEVELOPMENT IS THE PRESENCE OF WEAK MESOSCALE AND
BACKGROUND LARGE-SCALE ASCENT...AS WELL AS 50+ KT SWLY FLOW
SPREADING ACROSS THE LINE OF LOW-LEVEL FORCING...WHICH MAY FAVOR A
DISCRETE CONVECTIVE MODE DURING THE INITIAL STAGES OF THIS
CONVECTIVE EVENT. GIVEN THE POTENTIAL FOR SUPERCELLS...AND
STRENGTHENING LOW-LEVEL VERTICAL WIND SHEAR /I.E. EFFECTIVE SRH
ACROSS THE WARM SECTOR EXCEEDING 200 M2 S-2 DURING THE AFTERNOON
HOURS AS SLY LLJ INCREASES TO 40 KT/...A FEW TORNADOES WILL BE
POSSIBLE IN ADDITION TO LARGE HAIL AND DAMAGING WIND GUSTS.

..GARNER.. 11/07/2011