WATCHES: Severe Thunderstorm Watch Number 641

WWUS20 KWNS 020611
SEL1
SPC WW 020611
IAZ000-MNZ000-NEZ000-SDZ000-021400-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 641
NWS STORM PREDICTION CENTER NORMAN OK
115 AM CDT THU SEP 2 2010

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

NORTHWEST IOWA
SOUTHWEST MINNESOTA
NORTHEAST NEBRASKA
SOUTHEAST SOUTH DAKOTA

EFFECTIVE THIS THURSDAY MORNING FROM 115 AM UNTIL 900 AM CDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 60
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 95
STATUTE MILES EAST AND WEST OF A LINE FROM 50 MILES NORTH
NORTHWEST OF WORTHINGTON MINNESOTA TO 40 MILES WEST SOUTHWEST OF
NORFOLK NEBRASKA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).

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 640...

DISCUSSION...TSTMS EXPECTED TO CONTINUE FORMING IN MOIST AXIS
DOWNSTREAM FROM ZONE OF ASCENT ASSOCIATED WITH AMPLIFYING SHORTWAVE
TROUGH OVER THE DAKOTAS. COMBINATION OF MID LVL COOLING...FAIRLY
RICH LOW LVL MOISTURE...AND 40+ KT WLY MID LVL FLOW MAY SUPPORT A
FEW SUSTAINED STORMS/SUPERCELLS WITH A THREAT FOR HAIL AND POSSIBLY
LOCALLY DMGG WIND.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 50
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM
MOTION VECTOR 27030.

...CORFIDI

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.