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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 592

NWS STORM PREDICTION CENTER NORMAN OK

940 PM CDT SUN JUL 3 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       EASTERN MONTANA

       WESTERN NORTH DAKOTA



EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 940 PM UNTIL

400 AM CDT.



HAIL TO 1.5 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 105

STATUTE MILES EAST AND WEST OF A LINE FROM 60 MILES NORTH

NORTHEAST OF WILLISTON NORTH DAKOTA TO 45 MILES SOUTHWEST OF

BAKER MONTANA.  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 589...WW 590...WW 591...



DISCUSSION...SUPERCELLS IN NRN MT EXPECTED TO CONTINUE GENERALLY

ENEWD THROUGH EARLY MON.  WHILE LOW LVL CINH WILL SLOWLY INCREASE AS

BOUNDARY LAYER COOLS LATER THIS EVE...ANY ASSOCIATED DETRIMENTAL

EFFECT ON EXISTING STORMS MAY BE OFFSET BY INCREASING LOW LVL

MOISTURE PRESENT WITH ERN EXTENT.  BROKEN SQLN OF STORMS IN SE MT

ALSO SHOULD CONTINUE GENERALLY ENE.  EMBEDDED BOWING SEGMENTS MAY

CONTINUE TO POSE A THREAT FOR LOCALLY DMGG WIND FOR AWHILE ACROSS

THE REMAINDER OF SE MT...WHERE WW 590 WILL BE LOCALLY EXTENDED.

INCREASING CINH AND WEAKER FORCING FOR ASCENT/DEEP WIND

SHOULD...HOWEVER...ULTIMATELY CAUSE LINE TO WEAKEN OVER SW ND LATER

TNGT OR EARLY MON.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM

MOTION VECTOR 25035.





...CORFIDI

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