NORTHEAST ILLINOIS AND NORTHWEST INDIANA.
.DAY ONE...TONIGHT.
WEATHER HAZARDS EXPECTED:
OPPRESSIVE HEAT AND HUMIDITY.
THUNDERSTORMS...SOME MAY PRODUCE:
TORRENTIAL RAINFALL.
WINDS OVER 60 MPH.
AND FREQUENT CLOUD TO GROUND LIGHTNING.
AREAS AFFECTED AND TIMING:
DANGEROUS HEAT WILL ABATE BY THIS EVENING NORTH OF INTERSTATE
80 WITH MORE TOLERABLE CONDITIONS EXPECTED. HOWEVER...THE
DANGEROUS HEAT AND HUMIDITY WILL CONTINUE TONIGHT SOUTH OF
INTERSTATE 80.
THERE IS A SLIGHT CHANCE OF THUNDERSTORMS THIS AFTERNOON AND EVENING.
THERE IS A BETTER CHANCE OF STORMS AND LOCALLY HEAVY RAINFALL
AFTER MIDNIGHT TONIGHT...ESPECIALLY NORTH OF INTERSTATES 88 AND
290 ACROSS NORTHERN ILLINOIS.
DISCUSSION:
HEAT INDICES WILL REMAIN OVER 100 DEGREES THIS AFTERNOON...WITH
READINGS OVER 110 SOUTH OF INTERSTATE 80.
A WEAK FRONT MOVING ACROSS FAR NORTHERN ILLINOIS THIS
AFTERNOON IS BRINGING WITH IT SOME SLIGHT RELIEF TO THE HEAT AND
HUMIDITY. THERE IS A SMALL CHANCE THAT THUNDERSTORMS COULD
DEVELOP ALONG THE FRONT THIS AFTERNOON. GIVEN THE EXTREMELY
UNSTABLE ATMOSPHERE...ANY STORM THAT DOES DEVELOP WOULD HAVE
SOME POTENTIAL TO BE SEVERE...ESPECIALLY SOUTH OF THE KANKAKEE
AND ILLINOIS RIVERS...BUT THE THREAT APPEARS QUITE LIMITED AT
THIS TIME.
A COMPLEX OF THUNDERSTORMS SHOULD DEVELOP OVER IOWA THIS EVENING
AND TRACK INTO SOUTHERN WISCONSIN OR NORTHERN ILLINOIS VERY LATE
TONIGHT. WHILE THERE WOULD BE SOME POTENTIAL FOR LOCALLY
DAMAGING WINDS ALONG THE LEADING EDGE OF THE STORMS...THE
GREATER THREAT WOULD LIKELY BE HEAVY RAINFALL AND POSSIBLY EVEN
LOCALIZED FLASH FLOODING. THERE IS A GREAT DEAL OF UNCERTAINTY
ABOUT WHERE THIS COMPLEX OF THUNDERSTORMS WILL TRACK.
HOWEVER...IT APPEARS THAT AREAS OF NORTHERN ILLINOIS ALONG AND
NORTH OF INTERSTATE 88 WILL HAVE THE HIGHEST THREAT.
.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.
HEAT INDICES OVER 100 DEGREES ARE POSSIBLE FRIDAY SOUTH OF THE
KANKAKEE AND ILLINOIS RIVERS AND ACROSS MUCH OF THE AREA OVER THE
WEEKEND.
THERE WILL ALSO BE A THREAT FOR A PERIOD OR TWO OF THUNDERSTORMS
FRIDAY INTO THE WEEKEND.
THERE IS A SLIGHT CHANCE OF THUNDERSTORMS AGAIN BY NEXT
WEDNESDAY.
.SPOTTER INFORMATION STATEMENT...
SPOTTERS MAY BE NEEDED VERY LATE TONIGHT INTO FRIDAY.
&&
COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO
WEBPAGE: WEATHER.GOV/CHICAGO
