NORTHEAST ILLINOIS AND NORTHWEST INDIANA.
.DAY ONE...THIS AFTERNOON AND TONIGHT.
WEATHER HAZARDS EXPECTED:
THUNDERSTORMS...SOME COULD PRODUCE:
DAMAGING WINDS IN EXCESS OF 60 MPH.
HAIL TO THE SIZE OF QUARTERS.
FREQUENT CLOUD TO GROUND LIGHTNING.
MODERATE TO HEAVY RAIN.
AREAS AFFECTED AND TIMING:
A COLD FRONT WILL MOVE SOUTHEAST ACROSS THE REGION TODAY.
THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE FRONT LATE
THIS AFTERNOON INTO THE EVENING. THESE THUNDERSTORMS ARE
EXPECTED TO DEVELOP ALONG AND SOUTHEAST OF A LINE FROM GARY
INDIANA TO PONTIAC ILLINOIS.
DISCUSSION:
STRONG INSTABILITY WILL DEVELOP AHEAD OF A COLD FRONT
TODAY...HOWEVER A STRONG CAPPING INVERSION WILL KEEP
THUNDERSTORMS FROM FORMING INITIALLY. HOWEVER...AS A POTENT
UPPER LEVEL DISTURBANCE APPROACHES THE AREA LATER THIS
AFTERNOON...ITS DYNAMICS WILL INTERACT WITH THE LOW LEVEL
CONVERGENCE ALONG THE SURFACE FRONTAL ZONE TO WEAKEN AND BREAK
THROUGH THE CAP. THIS IS EXPECTED TO RESULT IN EXPLOSIVE
THUNDERSTORM DEVELOPMENT LATER THIS AFTERNOON. THE ATMOSPHERE
IN WHICH THESE STORMS DEVELOP WILL SUPPORT STRONG TO SEVERE
THUNDERSTORMS.
.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.
THERE IS A CHANCE OF THUNDERSTORMS SUNDAY NIGHT THROUGH MONDAY
NIGHT.
.SPOTTER INFORMATION STATEMENT...
SPOTTERS MAY BE NEEDED THIS AFTERNOON.
&&
COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO
WEBPAGE: WEATHER.GOV/CHICAGO
