

017 

WWUS20 KWNS 212047

SEL2

SPC WW 212047

COZ000-NMZ000-OKZ000-TXZ000-220300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 72

NWS STORM PREDICTION CENTER NORMAN OK

250 PM MDT WED APR 21 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHEAST COLORADO

       NORTHEAST NEW MEXICO

       THE EXTREME WESTERN OKLAHOMA PANHANDLE

       EXTREME NORTHWEST TEXAS PANHANDLE



EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 250 PM UNTIL

900 PM MDT.



HAIL TO 1.5 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 55

STATUTE MILES EAST AND WEST OF A LINE FROM 15 MILES WEST

NORTHWEST OF LA JUNTA COLORADO TO 50 MILES SOUTHWEST OF DALHART

TEXAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED

WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).



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.



DISCUSSION...WIDELY SCATTERED THUNDERSTORMS ARE DEVELOPING IN THE

ZONE OF STRONGER SURFACE HEATING AND LOW-LEVEL UPSLOPE FLOW ACROSS

NE NM/SE CO.  THE ENVIRONMENT THROUGH THE EVENING WILL BE

CHARACTERIZED BY SUFFICIENT INSTABILITY AND DEEP-LAYER VERTICAL

SHEAR FOR SUPERCELLS...WITH LARGE HAIL THE PRIMARY SEVERE STORM

THREAT.



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

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM

MOTION VECTOR 32015.





...THOMPSON

