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WWUS20 KWNS 261741

SEL8

SPC WW 261741

MNZ000-LSZ000-270300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 908

NWS STORM PREDICTION CENTER NORMAN OK

1240 PM CDT FRI SEP 26 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN MINNESOTA

       LAKE SUPERIOR



EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 1240 PM UNTIL

1000 PM 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 50 MILES WEST

NORTHWEST OF ELY MINNESOTA TO 25 MILES SOUTHWEST OF BRAINERD

MINNESOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).



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.



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

INTENSITY THIS AFTERNOON ALONG COLD FRONT AND IN ADVANCE OF SHORT

WAVE TROUGH TRANSLATING EWD INTO THE REGION.  DAYTIME

HEATING...MODEST BOUNDARY LAYER MOISTURE AND STEEP MIDLEVEL LAPSE

RATES WILL ALL CONTRIBUTE TO A DECREASING CAP AND THE DEVELOPMENT OF

MODERATE INSTABILITY WITH MLCAPE APPROACHING 2000 J/KG.  AS

SUCH...ONGOING ELEVATED STORMS ARE EXPECTED TO BECOME PROGRESSIVELY

SURFACE-BASED WITHIN AN ENVIRONMENT OF STRENGTHENING VERTICAL SHEAR

WHICH WILL ATTEND SHORT WAVE TROUGH.  THUS...POTENTIAL WILL EXIST

FOR A FEW SUPERCELL STRUCTURES CAPABLE OF LARGE HAIL AND DAMAGING

WIND GUSTS.



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 24030.





...MEAD/HALES

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