NORTHEAST ILLINOIS AND NORTHWEST INDIANA.
.DAY ONE...TONIGHT.
WEATHER HAZARDS EXPECTED:
THUNDERSTORMS...A FEW MAY PRODUCE:
STRONG DAMAGING WIND GUSTS IN EXCESS OF 60 MPH.
HAIL TO 1 INCH IN DIAMETER.
FREQUENT LIGHTNING.
AREAS AFFECTED AND TIMING:
SCATTERED THUNDERSTORMS WERE OCCURRING ACROSS FAR NORTHERN
ILLINOIS LATE THIS AFTERNOON...AND WILL CONTINUE TO MOVE
SOUTHEAST ACROSS THE REMAINDER OF NORTHERN ILLINOIS AND NORTHWEST
INDIANA THROUGH THE EARLY TO MID EVENING HOURS.
DISCUSSION:
A SLOW MOVING COLD FRONT WAS LOCATED ALONG THE ILLINOIS WISCONSIN
BORDER THIS AFTERNOON...EXTENDING WEST INTO NORTH CENTRAL IOWA.
SCATTERED THUNDERSTORMS HAVE DEVELOPED ALONG AND SLIGHTLY AHEAD
OF THIS FRONT...AIDED BY AN UPPER LEVEL DISTURBANCE WHICH WAS
MOVING SOUTHEAST ACROSS THE UPPER MIDWEST. THUNDERSTORMS WILL
LIKELY CONTINUE TO DEVELOP AND INCREASE IN INTENSITY ACROSS FAR
NORTHERN ILLINOIS DURING THE REMAINDER OF THE LATE AFTERNOON
HOURS...AND WILL LIKELY MOVE INTO NORTHWEST INDIANA AND AREAS
ALONG AND SOUTH OF INTERSTATE 80 IN ILLINOIS BY EVENING.
THUNDERSTORMS WILL THEN LIKELY DIMINISH IN BOTH COVERAGE AND
INTENSITY DURING THE MID AND LATE EVENING HOURS AS THE FRONT
CONTINUES TO PUSH SOUTHEAST INTO CENTRAL ILLINOIS AND CENTRAL
INDIANA.
SOME THUNDERSTORMS WILL HAVE THE POTENTIAL TO BE SEVERE DURING
THE REMAINDER OF THE AFTERNOON AND EARLY EVENING HOURS...DURING
THE PEAK HEATING AND INSTABILITY OF THE DAY. THIS INSTABILITY
COMBINED WITH RELATIVELY FAST MID LEVEL WINDS ASSOCIATED WITH THE
UPPER DISTURBANCE WILL SUPPORT THE THREAT OF DAMAGING WINDS IN
EXCESS OF 60 MPH AND HAIL TO 1 INCH IN DIAMETER FROM THE
STRONGEST STORMS.
.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.
ADDITIONAL ROUNDS OF THUNDERSTORMS ARE POSSIBLE ON MONDAY SOUTH
OF THE KANKAKEE AND ILLINOIS RIVERS. THERE IS A CHANCE OF THUNDERSTORMS
ACROSS MUCH OF THE OUTLOOK AREA MONDAY NIGHT AND TUESDAY... AND
AGAIN FRIDAY INTO SATURDAY.
.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE NECESSARY THROUGH THIS EVENING.
&&
COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO
WEBPAGE: WEATHER.GOV/CHICAGO
