


Area Forecast Discussion
Issued by NWS Central Illinois
Issued by NWS Central Illinois
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526 FXUS63 KILX 151734 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 1234 PM CDT Wed Oct 15 2025 .KEY MESSAGES... - Seasonably warm and mostly dry weather sticks around through Friday. - Widespread showers and thunderstorms are expected late Friday night through Saturday night. This will bring beneficial rainfall as well as a threat for severe weather on Saturday near and south of I-72. && .DISCUSSION... Issued at 228 AM CDT Wed Oct 15 2025 Surface high pressure is centered over the western Great Lakes Region early this morning with ridging extending south of there through a good portion of the central US. An ill defined cold/stationary front remains draped over the area, which will keep cloud cover persistent for most through tonight. Radar mosaic shows isolated to scattered shower activity ongoing over north-central parts of the state where weak upper forcing ripples through an upper ridge aloft. Although better chances for rain will stay north of here, a few brief showers (<15% chance) may clip areas near and north of I-74 today. Seasonably warm and mostly dry weather will continue through the end of the week with a pattern change coming by the weekend. A strong upper low positioned over the southwest US this morning will eject into the Northern Plains Thursday night, sending an attendant surface low toward the Hudson Bay by the weekend. A trailing cold front will work through central Illinois sometime on Saturday, bringing beneficial rainfall and perhaps some strong to severe storms. Somewhat better agreement amongst models shows the front approaching west-central parts of the state by midday, which would favor moderate instability building out ahead of the front by Saturday afternoon (up to 1000 J/kg) in a strongly sheared environment (0-6 km over 50 kt). If these parameters are realized, we could see strong to severe storms develop Saturday afternoon and evening, especially near/south of I-72 where SPC has a 15% risk. Beneficial and at times heavy rainfall is also expected with the weekend storms. Climatologically high PWATS exceeding 1.5" and mean flow nearly parallel to the front would support training thunderstorms capable of high rainfall rates. Rainfall probabilities have come up a bit with a 30-50% chance for 1" or more areawide and about a 10-20% chance of over 2" (highest in southeast IL). Shower activity may linger into Sunday as lapse rates steepen in breezy northwest flow behind the front. Temperatures cool back near seasonal normals behind the weekend system, with highs through early next week topping out in the 60s to near 70 degrees. Additional chances for rain are possible by the middle of next week under a more progressive upper pattern. NMA && .AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 1232 PM CDT Wed Oct 15 2025 Lower end VFR conditions continue through much of the day BKN to OVC sky coverage is expected with some light virga to showers possible across primarily the western portion of the forecast area. Winds remain light and variable through the daytime hours before accelerating and becoming more easterly after sunset. && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...NMA AVIATION...WFO ILX