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750 

WWUS20 KWNS 260116

SEL2

SPC WW 260116

MTZ000-NEZ000-SDZ000-260600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 552

NWS STORM PREDICTION CENTER NORMAN OK

815 PM CDT SAT JUN 25 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       MONTANA

       NORTHERN NEBRASKA

       SOUTHWESTERN SOUTH DAKOTA



EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 815 PM

UNTIL 100 AM 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 85

STATUTE MILES EAST AND WEST OF A LINE FROM 85 MILES NORTH

NORTHWEST OF PHILIP SOUTH DAKOTA TO 55 MILES SOUTH SOUTHWEST OF

VALENTINE NEBRASKA.  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...CONTINUE...WW 550...WW 551...



DISCUSSION...STORMS MOVING NEWD OFF THE HIGHER TERRAIN OF WY ARE

SPREADING NEWD INTO SWRN SD...WRN AND NRN NEB WHERE MODERATE

INSTABILITY EXISTS ALONG WITH 40-50 KT VERTICAL SHEAR...SUPPORTIVE

OF SUPERCELLS AND BOWING SEGMENTS. DESPITE A COOLING BOUNDARY

LAYER...STORMS MAY HAVE THE POTENTIAL TO PRODUCE ISOLATED DAMAGING

WIND AND LARGE HAIL THE REMAINDER OF THE EVENING AS THEY DEVELOP

NEWD.



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 24035.





...DIAL

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