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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 515

NWS STORM PREDICTION CENTER NORMAN OK

705 PM MDT TUE JUL 24 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN AND CENTRAL NORTH DAKOTA

       NORTHWEST AND NORTH-CENTRAL SOUTH DAKOTA



EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 705 PM

UNTIL 200 AM MDT.



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 NORTH AND SOUTH OF A LINE FROM 65 MILES WEST

SOUTHWEST OF DICKINSON NORTH DAKOTA TO 30 MILES SOUTH SOUTHEAST

OF JAMESTOWN NORTH DAKOTA.  FOR A COMPLETE DEPICTION OF THE WATCH

SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).



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 514...



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

INTENSITY THIS EVENING ALONG COOL SIDE OF SURFACE BOUNDARY WHERE THE

00Z BIS SOUNDING SHOWED A SUBSTANTIALLY WEAKER CAP THAN THAT

OBSERVED AT UNR AND ABR.  GIVEN THE MOIST...MODERATELY UNSTABLE AIR

MASS IN PLACE AND 40-50 KT OF DEEP-LAYER SHEAR...SETUP WILL FAVOR

EVOLUTION OF SUPERCELL AND BOWING STRUCTURES WITH A RISK FOR 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 28015.





...MEAD

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