


Area Forecast Discussion
Issued by NWS Central Illinois
Issued by NWS Central Illinois
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354 FXUS63 KILX 170741 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 241 AM CDT Thu Jul 17 2025 .KEY MESSAGES... - Daily storm chances remain into the extended. The next best chance for severe weather comes Saturday. - Heat and humidity will build next week...with early projections suggesting heat index values climbing well above 100 degrees by next Tuesday through much of the week. && .DISCUSSION... Issued at 241 AM CDT Thu Jul 17 2025 The best chance for showers and/or thunderstorms today is south of the I-72 corridor. The front will be draped over southeastern IL today. There is a marginal risk for damaging winds in the area of the front, but overall the storms should remain sub severe today. With the front stalling out over southeastern IL, daily chances for showers and thunderstorms exist into the weekend. Saturday the front will shift northward and a couple shortwave pulses are expected to move over the forecast area, which will bring the next best chance for wider coverage of convection and potentially severe weather. The NAMNest and FV3 models are showing a bowing complex moving into the area by the end of their runs from Iowa, so we will be monitoring the development and trends of that complex as we move forward. SPC has introduced a marginal risk for severe weather for Saturday (day 3). Timing of these waves is uncertain. Precipitation amounts over the weekend look to be in the 1-2 inch range. Today will be a good break from the muggy, warmth of the summer, but it won`t last long. Temperatures warm back into the upper 80s to low 90s by the weekend and they will continue to rise into the new week. Productive southerly flow will increase the WAA and moisture transport will usher in oppressive and sweltering temperatures. By Tuesday, daytime highs will get into the mid 90s with heat indices around 105-115 degrees. That looks to last most of the week. A heat advisory, maybe even an extreme heat headline, may be needed next week for the oppressive heat. Copple && .AVIATION... (For the 06z TAFs through 06z Thursday Night) Issued at 1225 AM CDT Thu Jul 17 2025 A cold front is draped across central Illinois late this evening with light southwest winds veering to northwest in its wake. Confidence in precip with frontal passage continues to diminish, and while not zero especially at SPI/DEC, the chances are better for precip to remain south of the terminals overnight. Meanwhile, MVFR/IFR ceilings currently over much of the Upper Midwest are expected to spread southeast across central Illinois Thursday morning. Ceilings are expected to lift/scatter to VFR around midday, but may return later in the evening as winds continue to veer to the northeast under the influence of high pressure building across the Upper Midwest. Deubelbeiss && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$