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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 182

NWS STORM PREDICTION CENTER NORMAN OK

500 PM CDT MON MAY 17 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL TEXAS



EFFECTIVE THIS MONDAY AFTERNOON FROM 500 PM UNTIL MIDNIGHT 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 60

STATUTE MILES EITHER SIDE OF A LINE FROM 55 MILES NORTH NORTHEAST

OF HUNTSVILLE TEXAS TO 105 MILES SOUTHWEST OF SAN ANGELO 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.



OTHER WATCH INFORMATION...THIS SEVERE THUNDERSTORM WATCH REPLACES

SEVERE THUNDERSTORM WATCH NUMBER 178. WATCH NUMBER 178 WILL NOT

BE IN EFFECT AFTER 500 PM CDT. CONTINUE...WW 179...WW 180...WW

181...



DISCUSSION...ROBUST MULTICELLULAR STORMS SHOULD CONTINUE TO ERUPT IN

VERY UNSTABLE AIR MASS ACROSS CENTRAL TEXAS THIS EVENING. SOME OF

THIS ACTIVITY WILL BE DRIVEN BY OUTFLOW ALONG LEADING EDGE OF

STRATIFORM RAIN REGION AND ASSOCIATED WITH LONG-LIVED MCS NOW MOVING

SOUTH AND EAST OF DFW AREA. TRAILING OUTFLOW IS MOVING INTO WEAKLY

CAPPED AND VOLATILE AIR MASS THAT SHOULD ALLOW FOR ADDITIONAL STORM

DEVELOPMENT OVER THE NEXT SEVERAL HOURS. WEAK LOW LEVEL S/SELY FLOW

TOPPED BY MID-LEVEL WNW FLOW ABOUT 20 KT EXPECTED TO CONTINUE TO

SUPPORT MARGINAL STORM ORGANIZATION. GREATER WIND POTENTIAL WILL

EXIST WITH MULTICELL MERGERS/COLLISIONS WHILE HAIL TO GOLF BALL SIZE

MAY OCCUR WITH INITIAL DISCRETE CONVECTION GIVEN MAGNITUDE OF

INSTABILITY/LAPSE RATES. OVERALL SLOW MOVEMENT...ESPECIALLY ALONG

TRAILING EDGE OF MCS OUTFLOW...COULD ALSO RESULT IN EXCESSIVE

RAINFALL.



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 30025.





...CARBIN

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