Area Forecast Discussion
Issued by NWS Central Illinois
Issued by NWS Central Illinois
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302 FXUS63 KILX 060634 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 134 AM CDT Sun Sep 6 2026 .KEY MESSAGES... - Welcomed relief is in store for today and Monday, with high temperatures in the 80s for most locations and dropping heat indices into the 80s, near 90. - High heat and humidity return Tuesday and Wednesday. Wednesday looks to be the hottest, bringing another risk for triple- digit heat index values. There is a 20-30% chance of heat indices greater than 100 degrees south of I-70 Wednesday afternoon. && .DISCUSSION... Issued at 134 AM CDT Sun Sep 6 2026 A backdoor cold front pushed into the area yesterday evening, which will bring "relief" today and Monday, where heat indices will be in the mid 80s to near 90 and highs in the 80s to low 90s. These cooler temperatures will warm back up to low to upper 90s by Tuesday and Wednesday as the upper ridging builds back eastward once again. There is a 20-30% chance of heat indices greater than 100 degrees south of I-70 Wednesday afternoon, from the LREF. A weak cold front will move through on Wednesday as the ridge gets broken down by an upper low, potentially stalling out across IL. It will bring another two day break from the sweltering mid to upper 90 temperatures, dropping temperatures into the low to mid 80s before building back to near 90 for the weekend. The next chance for any rain will come Thursday with the greatest POPs (50-70%) mainly near and south of I-72. A strengthening LLJ will reinvigorate thunderstorm development along the stalled boundary. As of now, the machine learning models are not showing a severe threat with these storms. The PWATs look to be around 1.8-2.2 inches and WPC has a marginal risk for excessive rainfall for day 5 (Thursday). && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 1209 AM CDT Sun Sep 6 2026 An area of ceilings just above 1,000 feet is pushing southwest, with the leading edge extending from about KBMI-KCMI this hour. The low clouds are guided by northeast winds near 10 knots. Model guidance and ensembles are suggesting about a 4-5 hour period of MVFR conditions at each TAF site, and the band of low clouds should be southwest of the terminals by 12-13z. After that, clouds into Sunday evening should just be scattered. Northeast winds will prevail through the period. Some winds near 10 knots are occurring near the leading edge of the cloud deck and should subside for a time, but pick up again Sunday morning after skies clear. && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$ KEY MESSAGES...Copple DISCUSSION...Copple AVIATION...Geelhart