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WWUS20 KWNS 262303

SEL4

SPC WW 262303

MTZ000-SDZ000-WYZ000-270600-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 224

NWS STORM PREDICTION CENTER NORMAN OK

505 PM MDT WED MAY 26 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       SOUTHEAST MONTANA

       WESTERN SOUTH DAKOTA

       NORTHEAST WYOMING



EFFECTIVE THIS WEDNESDAY AFTERNOON FROM 505 PM UNTIL MIDNIGHT MDT.



TORNADOES...HAIL TO 2 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 80 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 100 MILES NORTHWEST OF

SHERIDAN WYOMING TO 35 MILES NORTHEAST OF RAPID CITY SOUTH

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

WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).



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 223...



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

INTENSITY THIS EVENING WITHIN A NW-SE ORIENTED ZONE OF SUSTAINED

LOW-LEVEL CONVERGENCE.  A MOISTENING/DESTABILIZING BOUNDARY LAYER IN

CONJUNCTION WITH A STRENGTHENING DEEP-LAYER WIND FIELD WILL RESULT

IN AN INCREASINGLY FAVORABLE ENVIRONMENT FOR SUPERCELLS CAPABLE OF

LARGE HAIL AND TORNADOES.



AVIATION...TORNADOES AND 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 23025.





...MEAD/CORFIDI

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