

518 

WWUS20 KWNS 190354

SEL2

SPC WW 190354

MNZ000-191000-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 472

NWS STORM PREDICTION CENTER NORMAN OK

1050 PM CDT THU JUN 18 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       PARTS OF EAST-CENTRAL AND SOUTHERN MINNESOTA



EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 1050 PM

UNTIL 500 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 60

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 40 MILES SOUTH

SOUTHWEST OF REDWOOD FALLS MINNESOTA TO 15 MILES NORTHEAST OF

MINNEAPOLIS MINNESOTA.  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...THIS SEVERE THUNDERSTORM WATCH REPLACES

TORNADO WATCH NUMBER 467. WATCH NUMBER 467 WILL NOT BE IN EFFECT

AFTER 1050 PM CDT. CONTINUE...WW 469...WW 470...WW 471...



DISCUSSION...MOIST/MODERATELY-UNSTABLE AIRMASS PERSISTS ACROSS PARTS

OF THE SRN HALF OF MN...AHEAD OF A NE-SW BAND OF SCATTERED SHOWERS

AND THUNDERSTORMS.  WHILE THIS CONVECTION HAS WEAKENED OVER THE PAST

COUPLE OF HOURS...WELL-DEFINED UPPER SYSTEM CENTERED OVER NRN MN

CONTINUES TO SHIFT SLOWLY EWD -- WHICH SHOULD CONTINUE TO SUPPORT

SOME POTENTIAL FOR CONVECTIVE REDEVELOPMENT OVER THE NEXT FEW HOURS.

 WITH FAVORABLE SHEAR IN PLACE ACROSS THE AREA...ANY DEVELOPING

STORMS WOULD LIKELY BECOME SUPERCELLULAR -- ALONG WITH ASSOCIATED

POTENTIAL FOR LARGE HAIL AND DAMAGING WINDS.  IN

ADDITION...LOW-LEVEL VEERING WITH HEIGHT SUGGESTS A LIMITED THREAT

FOR AN ISOLATED/BRIEF TORNADO WITH ANY SUSTAINED SUPERCELL.



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 26030.





...GOSS

