textproduct: Central Illinois

KEY MESSAGES

- A stretch of warm weather is expected to begin Sunday and last through Friday, with daily highs in the upper 70s and lower 80s, and even mid 80s likely on Tuesday. Gusty south to southwest winds, occasionally reaching 30-40 mph, will accompany this warm period.

- Unsettled weather is expected much of the upcoming week, with daily chances of showers and thunderstorms. Severe storms are also a risk on Tuesday and Wednesday, with Tuesday currently exhibits the highest probability (15-30%) of severe weather.

DISCUSSION

Issued at 245 PM CDT Sat Apr 11 2026

The mid afternoon surface map shows 1033 mb high pressure Lake Huron and Lake Erie and ridging into northeast IL. A warm front extended from southwest MO into central Nebraska. Some convection was pushing eastward into eastern and southern parts of Iowa and northern MO while isolated convection was in eastern MO and far sw IL into sw KY ahead of the warm front. Clouds were increasing over central and nw IL today (cloud bases 3-6k ft from I-55 nw) while more peaks of sunshine in eastern IL. Temps were mostly in the low to mid 60s over much of central IL at 2 pm, but ranged from 55-60F nw of the IL river to upper 60s to around 70F in southeast IL from I-70 south.

The latest CAMs have showers and isolated thunderstorms brushing areas nw of the IL river late this afternoon and evening.A few members like the ARW have very isolated convection lifting toward sw CWA by mid to late evening, but most of the members have this diurnally driven convection diminishing after sunset. A warm front to lift ne over central/se IL overnight as SE winds shift south to SSW and increase to breezy levels by sunrise Sunday morning. Milder lows tonight in the mid 50s to around 60F, mildest from Springfield sw.

Tight pressure gradient over IL in warm sector on Sunday with south to SW winds having gusts 30-40 mph by late morning/afternoon. HREF has 30-60% chance of wind gusts over 40 mph from I-55 nw on Sunday afternoon. Warmer highs Sunday in the upper 70s/lower 80s. After slight chance of convection over northern/nw CWA overnight into Sunday morning, will see increasing chances of convection further into central IL during Sunday afternoon and Sunday night, and into southeast IL overnight Sunday night. This due to short waves ejecting ne from Texas into IL along with increasing moisture. SPC keeps risk of severe storms well west/sw of IL Sunday afternoon and Sunday night. SPC Day3 outlook has severe risk mainly north and west of CWA, with marginal risk clipping far northern CWA for late Monday afternoon/Mon evening, with slight risk further north over central/southern WI into northern Iowa and southern half of MN where strong forcing will be. Breezy sw winds continue Monday with gusts to around 30 mph and warm highs in lower 80s, with mid 80s from Springfield sw toward MS river valley.

SPC has risk of severe storms over central IL from Paris to Shelbyville nw on Tue afternoon/Tue night and over much of central and southern IL on Wed with stronger forcing and instability around. SW winds gusting 25-35 mph on Tue to bring warm highs in the mid 80s over the area. Highs in the upper 70s Wed in central IL and lower 80s in southeast IL. A cold front to drop into northern IL on Thu and then pushes se through central IL later Fri night into Sat, likely bringing more showers and thunderstorms to CWA. Highs in the upper 70s/lower 80s Thu and lower 80s Friday, cool off next weekend behind a stronger cold front passing through. WPC has marginal risk of excessive rainfall over central/nw IL Tue/Tue night and across CWA Wed/Wed night.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 601 PM CDT Sat Apr 11 2026

Low pressure will move east across the northern Great Plains into the Upper Midwest tonight and tomorrow. Across central Illinois, a modest SE breeze currently in place will veer to the SSW and increase Sunday morning with gusts eventually topping out in the 25 to 35 kt range Sunday afternoon. Meanwhile, a few spotty showers are weakening as they approach central Illinois this evening with PIA having the best chance to see any precip on station. Otherwise VFR conditions are favored through the period.

ILX WATCHES/WARNINGS/ADVISORIES

None.