

924 

WWUS20 KWNS 292136

SEL0

SPC WW 292136

MTZ000-NDZ000-300600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 550

NWS STORM PREDICTION CENTER NORMAN OK

440 PM CDT THU JUL 29 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHEAST MONTANA

       NORTHWEST AND NORTH CENTRAL NORTH DAKOTA



EFFECTIVE THIS THURSDAY AFTERNOON AND FRIDAY MORNING FROM 440 PM

UNTIL 100 AM CDT.



HAIL TO 2.5 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 70

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 70 MILES WEST

SOUTHWEST OF GLASGOW MONTANA TO 70 MILES EAST SOUTHEAST OF MINOT

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

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).



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 548...WW 549...



DISCUSSION...SCATTERED THUNDERSTORMS ARE INCREASING OVER NORTHEAST

MT WHERE BACKED LOW LEVEL WINDS AND MODERATE INSTABILITY ARE

PRESENT.  OTHER STORMS ARE LIKELY TO FORM THIS EVENING OVER PORTIONS

OF NORTHWEST AND NORTH CENTRAL ND IN REGION OF RELATIVELY STRONG LOW

LEVEL WARM ADVECTION.  FAVORABLE EFFECTIVE SHEAR AND CAPE PARAMETERS

SUPPORT A RISK OF SUPERCELL STORMS CAPABLE OF LARGE HAIL AND

DAMAGING WINDS.



AVIATION...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 27030.





...HART

