

926 

WWUS20 KWNS 130645

SEL1

SPC WW 130645

ILZ000-INZ000-LMZ000-131500-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 901

NWS STORM PREDICTION CENTER NORMAN OK

145 AM CDT SAT SEP 13 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       NORTHERN ILLINOIS

       NORTHERN INDIANA

       LAKE MICHIGAN



EFFECTIVE THIS SATURDAY MORNING FROM 145 AM UNTIL 1000 AM CDT.



TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 60 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 45 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 30 MILES WEST NORTHWEST OF

MARSEILLES ILLINOIS TO 25 MILES SOUTHEAST OF FORT WAYNE INDIANA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU1).



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



OTHER WATCH INFORMATION...CONTINUE...WW 900...



DISCUSSION...INCREASED LOW LVL VEERING WIND PROFILES ALONG NE-MOVING

WARM FRONT...ALONG WITH FAIRLY RICH LOW LVL MOISTURE AND

STRENGTHENING WAA BENEATH ENTRANCE REGION OF HIGH LVL JET STREAK

OVER THE GRT LKS ...SUGGEST CONTINUE THREAT FOR STORMS WITH LOW LVL

ROTATION OVER PARTS OF NRN IL/IND /REF MCD 2258/.  ISOLD TORNADOES

WILL BE POSSIBLE WITH ANY MORE SUSTAINED/DISCRETE STORMS.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 50 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

450. MEAN STORM MOTION VECTOR 26030.





...CORFIDI

