Severe Thunderstorm Warning 46, NWS Chicago, IL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO IL
330 AM CDT THU AUG 2 2001

THUNDERSTORMS THAT DROPPED SOUTHEAST OUT OF SOUTHERN WI LAST EVENING
DIDN'T GET TOO FAR INTO NORTHERN IL BEFORE WEAKENING. EVEN THE
LINGERING SHOWERS IN NORTHEAST AND EAST CENTRAL IL HAVE ALL BUT
DISSIPATED. FRONTAL BOUNDARY EARLY THIS MORNING EXTENDING FROM
EASTERN LAKE SUPERIOR SOUTHWESTWARD ACROSS WI AND IA TO SOUTH
CENTRAL NEB WITH 3 DISTINCT AREAS OF ACTIVE CONVECTION...CENTRAL
HIGH PLAINS...NORTHERN IA AND SOUTHERN WI...WITH SOME FILLING IN
ALONG THE FRONT FROM WI TO IA. COMPARED TO CURRENT RADAR AND
SATELLITE IT APPEARS THAT THE AVN MODEL HAS THE BEST HANDLE ON THE
SITUATION PER ITS QPF...OMEGA AND ISENTROPIC FIELDS. FOLLOWING AVN
BRINGS UVV AND QPF MAX SOUTH-SOUTHEAST OUT OF SOUTHERN WI...ACROSS
NORTHEAST IL AND TO EAST CENTRAL IL AND NORTHWEST IND BY EVENING AS
SHORT WAVE ROTATES AROUND UPPER RIDGE ON SOUTHERN PERIPHERY OF
WESTERLIES. SOME HEAVIER RAINS POSSIBLE WITH SLOW MOVING CELL
MOVEMENT INDICATED ALONG WITH PRECIPITABLE WATER OF 2 TO 2 1/2
INCHES. FRONT TO ONLY MAKE SLOW PROGRESS AND AGAIN PREFER AVN HERE
WHICH IS SLOWEST IN PUSHING IT INTO NORTHWESTERN AND FAR
NORTHEASTERN IL THIS AFTERNOON...AND EVENTUALLY INTO CENTRAL IL
OVERNIGHT. CLOUDS AND LOCALLY COOLED AIR FROM TSRA SHOULD KEEP TEMPS
IN THE 85 TO 90 DEGREE RANGE. DEW POINTS STILL HIGH BUT HEAT INDEX
VALUES WILL BE BELOW HEADLINE THRESHOLD. WILL STILL KEEP MENTION OF
HUMID CONDITIONS IN FORECAST THOUGH. SLIGHTLY COOLER AND DRIER AIR
TO ARRIVE FRIDAY AS THE SURFACE RIDGE AND ITS LOWER 60S DEW POINTS
CURRENTLY OVER THE DAKOTAS MOVES EAST INTO THE WESTERN LAKES REGION.

.CHI...NONE.

TRS

ILZ003>006-008-010>014-019>023-032>033-039-INZ001>002-010>011-019-
021700-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO IL
600 AM CDT/EST THU AUG 2 2001

FOR NORTH CENTRAL AND NORTHEAST ILLINOIS AND NORTHWEST INDIANA...

NO HAZARDOUS WEATHER IS EXPECTED TODAY OR TONIGHT.

THERE WILL BE SOME THUNDERSTORMS TODAY AHEAD OF A COLD FRONT AS IT
SLOWLY MOVES SOUTHEASTWARD INTO NORTHERN ILLINOIS...BUT THEY ARE NOT
EXPECTED TO BE SEVERE.  THE COLD FRONT WILL MOVE THROUGH NORTHERN
ILLINOIS AND NORTHWEST INDIANA TONIGHT...ENDING THE THREAT OF STORMS
THIS EVENING.  AS HIGH PRESSURE MOVES EAST INTO THE UPPER MIDWEST
FRIDAY...A LITTLE COOLER AND DRIER AIR WILL SPREAD INTO TmHE AREA.

TRS