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479 

WWUS20 KWNS 262100

SEL3

SPC WW 262100

COZ000-KSZ000-NMZ000-OKZ000-TXZ000-270400-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 653

NWS STORM PREDICTION CENTER NORMAN OK

400 PM CDT WED SEP 26 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       FAR SOUTHEAST COLORADO

       SOUTHWEST KANSAS

       FAR NORTHEAST NEW MEXICO

       OKLAHOMA PANHANDLE

       TEXAS PANHANDLE



EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 400 PM UNTIL

1100 PM CDT.



HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

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



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 70

STATUTE MILES EAST AND WEST OF A LINE FROM 35 MILES SOUTH

SOUTHEAST OF AMARILLO TEXAS TO 45 MILES NORTH OF ELKHART KANSAS.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU3).



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 651...WW 652...



DISCUSSION...TSTMS CURRENTLY DEVELOPING ALONG THE RATON MESA ARE

EXPECTED TO INCREASE IN COVERAGE AND INTENSITY AS LOW-LEVEL UPSLOPE

FLOW IS ENHANCED BY THE GLANCING INFLUENCE OF A VORTICITY MAXIMUM

ROTATING AROUND PARENT UPPER LOW.  WHILE THE BOUNDARY LAYER IS NOT

OVERLY MOIST THE COMBINATION OF 45-55 F DEWPOINTS AND STEEP LAPSE

RATES ARE SUPPORTING MODEST INSTABILITY.  MOREOVER...30-35 KT WLY

MIDLEVEL FLOW OVERLAYS ELY SURFACE WINDS...RESULTING IN 40-45 KT OF

DEEP-LAYER SHEAR WHICH WILL SUPPORT SUPERCELLS CAPABLE OF MAINLY

LARGE HAIL AND DAMAGING WINDS.



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

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 28025.





...MEAD

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