NORTHEAST ILLINOIS AND NORTHWEST INDIANA.
.DAY ONE...TODAY AND TONIGHT.
WEATHER HAZARDS EXPECTED:
THUNDERSTORMS...SOME MAY PRODUCE:
HEAVY RAINFALL WITH FLASH FLOODING.
FREQUENT LIGHTNING.
DAMAGING WINDS IN EXCESS OF 60 MPH.
OPPRESSIVE HEAT AND HUMIDITY.
AREAS AFFECTED AND TIMING:
THUNDERSTORMS ALONG AND AHEAD OF A COLD FRONT WILL MOVE INTO
NORTHWESTERN ILLINOIS THIS MORNING AND THEN SPREAD SLOWLY SOUTH
AND EAST INTO EAST-CENTRAL ILLINOIS AND NORTHWESTERN INDIANA
LATER TODAY.
THE DANGEROUS HEAT AND HUMIDITY WILL CONTINUE...ESPECIALLY
SOUTH OF INTERSTATE 80.
DISCUSSION:
THUNDERSTORMS ARE EXPECTED TO BRING MORE HEAVY RAINFALL TO
NORTHERN ILLINOIS AND NORTHWESTERN INDIANA TODAY. SINCE THE
GROUND IS SATURATED AND AREA RIVERS SWOLLEN FROM THE VERY HEAVY
RAINFALL OF THE PAST FEW DAYS...IT WILL NOT TAKE VERY MUCH
ADDITIONAL RAINFALL TO BRING A RISK OF ADDITIONAL FLASH
FLOODING TO THE AREA. WITH A VERY MOIST AIRMASS IN PLACE AND
LITTLE PUSH BEHIND THE APPROACHING COLD FRONT...THUNDERSTORMS
WILL BE EFFICIENT RAIN PRODUCERS AND HEAVY RAINFALL IS LIKELY.
THUS THE FLASH FLOOD WATCH WILL REMAIN IN EFFECT FOR PORTIONS
OF THE AREA GENERALLY NORTH OF INTERSTATE 80.
LOCATIONS ON THE DES PLAINES AND DU PAGE RIVERS WILL REMAIN
ABOVE FLOOD STAGE THROUGH TONIGHT.
HEAT INDEX VALUES ARE EXPECTED TO RISE TO 110 TO 115 DEGREES
THIS AFTERNOON FOR LOCATIONS SOUTH OF THE ILLINOIS AND KANKAKEE
RIVERS
.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.
THERE WILL BE PERIODIC CHANCES FOR THUNDERSTORMS WEDNESDAY
THROUGH SATURDAY.
.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE NECESSARY TODAY...ESPECIALLY FOR FLASH
FLOODING AND STRONG...DAMAGING WINDS.
&&
COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO
WEBPAGE: WEATHER.GOV/CHICAGO
