267 
ACUS11 KWNS 222242
SWOMCD
SPC MCD 222241
ILZ000-INZ000-230100-

SPC MESOSCALE DISCUSSION 1433 FOR NCNTRL IL...WRN/NWRN IN 
CONCERNING...SEVERE THUNDERSTORM WATCH #521...

MARGINALLY SEVERE STORMS CONTINUE IN PORTIONS OF WW#521. WATCH WILL
CONTINUE TO REMAIN IN EFFECT ACROSS SRN AND ERN PORTIONS OF
WW...ALTHOUGH THERE IS A POSSIBILITY WW WILL BE CANCELLED AHEAD OF
PROPOSED EXPIRATION TIME AT 23/01Z. 

MODERATELY STRONG COLD FRONT CONTINUES TO AID IN TSTM DEVELOPMENT
IN PARTS OF WW#521. MESOANALYSIS REVEALS COLD FRONTAL AXIS LIES
FROM CNTRL LK MICHIGAN...THRU NERN AND NCNTRL IL...INTO NCNTRL MO.
CHICAGO VAD PROFILE DEPICTS WINDS HAVE BACKED TO THE NW...WHILE
NORTH WEBSTER VAD ALSO SHOWS RECENT BACKING TO NW INDICATIVE OF
IMPINGEMENT OF LARGE-SCALE FRONTAL PUSH THRU BOTH NERN IL AND NRN
IND. ISOLATED TO SCATTERED MARGINALLY SEVERE STORMS WILL CONTINUE
ALONG/AHEAD OF FRONTAL BOUNDARY MAINLY FROM AROUND
JACKSONVILLE...EWD TO DANVILLE...NEWD INTO MUCH OF NRN IND THE NEXT
FEW HOURS. RATHER WEAK DEEP LAYER SHEAR AND SR HELICITY VALUES
SUGGEST POOR STORM ORGANIZATION WITH SMALL HAIL/STRONG WINDS BEING
THE PRIMARY SEVERE THREATS.  

..NADEN.. 07/22/02

PLEASE SEE WWW.SPC.NOAA.GOV/ FOR GRAPHIC PRODUCT...