FXUS63 KLOT 100007
AFDCHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO IL
650 PM CDT WED JUL 9 2003

AVIATION DISCUSSIN FOR 00Z TAFS...

TSRA CONTS TO ERUPT ALONG STNRY BNDRY S OF TERMINALS AND EXPECTED TO 
REMAIN S NEXT FEW HRS AS OUTFLOW BALANCING STRENGTHENING SWRLY FLO 
PROVIDING VERY RICH UNSTABLE AIR INTO BNDRY AS SHORT WAV APPROACHES 
MID MS VALLEY. WMFNT TO LIFT NWRD LATER TNGT WITH CONVECTIVE 
ACTIVITY GRADUALLY MOVG INTO GYY 02Z AND CHI VC 04Z. TSRA WITH SHORT 
WAV TROF IN CNTRL/ERN IA TO CONT EWRD TO REACH RFD 02Z. WMFNT TO 
TEMPORARILY LIFT THRU CHI TERMINALS AS SFC LOW TRACKS SE ACROSS NE 
IA THEN AE NR WI/IL STATE LN. CDFNT TO SWING THRU DURG EARLY A.M. AS 
LOW CONTS E ACROSS SRN LAKE MI. CYCLONIC FLO AND LO LEVEL MOISTURE 
SHUD YIELD BKN TO OVC SC AFTER SOME HEATING THU MORNING.       

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PUBLIC DISCUSSION FOR PM ZONES/GRIDS...

LATEST BATCH OF SHRA/TSRA E OF I-55. NRN PORTION MOVG E AT 
50...WHILE STRONGER SRN PORTION MOVG E AT 30 CLOSER TO BOUNDARY. 
WILL BE EXITING SERN COUNTIES DURG LATE AFTERNOON AND EARLY EVE AS 
LEAD SHORT WAVE TROF CONTS E INTO IN. NEXT ROUND DEVELOPING OVER IA. 
CONT DVLPMNT EXPECTED INTO NRN IL AS LOW LEVEL FLO BACKS WITH 
ENHANCED CONVERGENCE/LIFT ALONG FRONTAL BOUNDARY EXTENDING FM E 
CNTRL IA SEWRD ACROSS N HALF OF IL INTO W CNTRL IND IN RESPONSE TO  
MAIN SHORT WAVE TROF MN/IA/MO ROTATING ACROSS MID MS VALLEY DURG 
EVE. TROF AND AND ASSOCIATED CDFNT CONTS THRU CFA OVERNIGHT AND 
EARLY THU. THIS SHUD TURN OFF TAP FOR A BIT WITH ANY SIG CHC OF SHRA 
CONFINED TO N OF IL STATE LN ON THU...CLOSER TO CENTER OF MID LEVEL 
LOW.  CHC OF THUNDERSHOWERS FRI AFTERNOON INTO EVE AND AGAIN SAT 
AFTERNOON INTO EVE WITH DAYTIME HEATING AND MINOR IMPULSES DROPPING 
SE INTO UPR TROF AXIS AS UPR LOW SLOWLY TRACKS ACROSS ONTARIO INTO 
QUEBEC.              



.CHI...NONE.
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