

538 

WWUS20 KWNS 260230

SEL3

SPC WW 260230

ILZ000-260700-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 553

NWS STORM PREDICTION CENTER NORMAN OK

935 PM CDT SAT JUN 25 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL ILLINOIS



EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 935 PM

UNTIL 200 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 45

STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES NORTHWEST OF

MATTOON ILLINOIS TO 30 MILES EAST SOUTHEAST OF SALEM ILLINOIS.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU3).



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 550...WW 551...WW 552...



DISCUSSION...CLUSTER OF ELEVATED STORMS WILL CONTINUE TO SPREAD

ESEWD TO THE N OF THE SURFACE WARM FRONT.  A FEED OF MODERATE

INSTABILITY FROM THE SW...AND DEEP-LAYER SHEAR SUFFICIENT FOR

SUPERCELLS...WILL MAINTAIN A CONTINUING RISK FOR LARGE HAIL AND

ISOLATED DAMAGING 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 30025.





...THOMPSON

