textproduct: Central Illinois

KEY MESSAGES

- Beneficial rainfall is on tap this week. The 12z Mar 2 LREF indicates a 50-70% chance of greater than 2 inches of rain from today through next Sunday morning along and south of a Jacksonville to Danville line.

- There is a Marginal Risk (5-15% chance) for severe weather along and south of the I-70 corridor Wednesday afternoon and evening. The primary threat with the storms will be large hail.

- Another severe weather risk may materialize late Friday. At this time, the highest probabilities for severe are focused west of the Mississippi River.

..Severe Weather Risk Late Friday

The low will track across central Illinois Wednesday night, then into the southern Great Lakes by Thursday. After a few lingering showers Thursday morning, a lull in the precip chances will be observed Thursday afternoon and night before the next round of convection materializes on Friday. The 00z Mar 3 GFS and ECMWF are in good agreement with the timing of the late-week synoptic features...with both models showing a warm front surging northward through central Illinois on Friday. Will need to keep an eye on any convection that fires along/north of the warm front Friday morning for the potential for hail: however, it appears forcing for additional convection will lift well north of the area Friday afternoon as the warm sector arrives in earnest, pushing high temperatures well into the 70s. Meanwhile low pressure lifting into the Upper Midwest will pull a strong cold front across the Plains Friday afternoon and evening...eventually pushing into the Illinois River Valley by 12z Sat. This is not particularly good timing for severe weather in central Illinois as instability will be at a minimum as the strongest forcing arrives. At this time, the highest probabilities for severe weather (greater than a 30% chance) remain focused west of the Mississippi River late Friday afternoon/evening. Stay tuned to later forecasts for additional details.

Barnes

AVIATION

(For the 12z TAFs through 12z Wednesday Morning) Issued at 552 AM CST Tue Mar 3 2026

IFR ceilings have overspread the central Illinois terminals early this morning and will remain locked in place for the balance of the day. Winds are currently SE at 5-10kt, but are progged to become NE after 20z/21z. At that time, drier air over northeast Illinois will trickle southwestward...potentially leading to an improvement to MVFR at KPIA/KBMI. Given expected wind direction and HRRR/RAP forecast, am most confident with rising ceilings at KPIA. Have therefore gone MVFR there after 20z, but have opted to maintain IFR at KBMI and the remaining sites through the entire 12z TAF period. 1130z/530am radar imagery shows showers with a few embedded thunderstorms lifting E/NE into central Illinois. Based on radar trends, have carried a period of thunder at both KSPI and KDEC through 15z. After that, there will be a temporary lull in the showers before a renewed round develops late this afternoon and evening. Models continue to suggest the most widespread convection will focus along/south of I-72, so have opted to mention thunder at KSPI/KDEC/KCMI between 01z and 06z before instability decreases and the showers gradually sink S/SE of the terminals.

Barnes

ILX WATCHES/WARNINGS/ADVISORIES

None.