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WWUS20 KWNS 112153

SEL5

SPC WW 112153

COZ000-KSZ000-NEZ000-120600-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 285

NWS STORM PREDICTION CENTER NORMAN OK

350 PM MDT WED MAY 11 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       NORTHEAST COLORADO

       NORTHWEST KANSAS

       SOUTHWEST AND SOUTH CENTRAL NEBRASKA



EFFECTIVE THIS WEDNESDAY AFTERNOON FROM 350 PM UNTIL MIDNIGHT MDT.



TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 50 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 75 MILES WEST OF BURLINGTON

COLORADO TO 55 MILES EAST NORTHEAST OF HILL CITY KANSAS.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU5).



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



OTHER WATCH INFORMATION...CONTINUE...WW 280...WW 281...WW

282...WW 283...WW 284...



DISCUSSION...TSTMS EXPECTED TO INCREASE IN COVERAGE AND STRENGTH

THROUGH THIS EVE AS EXIT REGION OF JET STREAK/UPR VORT ASSOCIATED

WITH CNTRL RCKYS UPR LOW PIVOTS NNEWD.  LOW LVL CONVERGENCE WILL

MAXIMIZE ALONG W-E FRONT THAT LIKELY WILL BECOME NEARLY STNRY ALONG

MAIN AXIS OF WW.  DEEP EML...AMPLE BOUNDARY LAYER MOISTURE...AND

STRENGTHENING DEEP SHEAR SUGGEST LIKELIHOOD FOR SUPERCELLS WITH

LARGE HAIL AND LOCALLY DMGG WIND...IN ADDITION TO POSSIBLE TORNADOES

IN ZONE OF MAXIMUM LOW LVL DIRECTIONAL SHEAR NEAR FRONT.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

500. MEAN STORM MOTION VECTOR 20025.





...CORFIDI

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