

000 

WWUS20 KWNS 210323

SEL8

SPC WW 210323

MNZ000-210900-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 628

NWS STORM PREDICTION CENTER NORMAN OK

1025 PM CDT MON AUG 20 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHERN AND CENTRAL MINNESOTA



EFFECTIVE THIS MONDAY NIGHT AND TUESDAY MORNING FROM 1025 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 65

STATUTE MILES EAST AND WEST OF A LINE FROM 55 MILES NORTHWEST OF

MINNEAPOLIS MINNESOTA TO 20 MILES WEST SOUTHWEST OF FAIRMONT

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.



OTHER WATCH INFORMATION...CONTINUE...WW 624...WW 625...WW

626...WW 627...



DISCUSSION...SLIGHTLY ELEVATED TSTMS/POSSIBLE SUPERCELLS WITH LARGE

HAIL EXPECTED  IN WAA AREA OVER PARTS OF MN THROUGH EARLY TUESDAY AS

RICH MOIST LAYER IS LIFTED AHEAD OF WEAK IMPULSE IN WLY FLOW ALOFT.

MODERATE UNIDIRECTIONAL WLY SHEAR IS PRESENT IN CLOUD LAYER THAT MAY

ENHANCE POTENTIAL FOR HAIL.



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 500. MEAN STORM

MOTION VECTOR 27030.





...CORFIDI

