textproduct: Central Illinois

KEY MESSAGES

- After near seasonable temperatures into Tuesday, much warmer air will arrive on breezy south to southwest winds Wednesday and Thursday. Near record highs in the low to mid 80s are expected on Thursday across central and southeast IL.

- Another chance (60-80%) for showers and thunderstorms will accompany a cold front later Thursday afternoon into Thursday night. There is at least a low severe thunderstorm risk across central and southeast IL Thursday afternoon and Thursday evening.

DISCUSSION

Issued at 230 PM CDT Mon Mar 23 2026

The 19Z/2 pm surface map shows 1031 mb Canadian high pressure over the upper MS river valley with north to NNW winds (breezier winds gusting 20-25 mph in eastern I) ushering in seasonably cool low to mid 40s over central/se IL. Very dry air too with dewpoints in the upper teens to mid 20s over central IL and upper 20s/lower 30s in southeast IL. The cumulus cloud field had broken up over areas from I-55 east early this afternoon while broken cirrus clouds moved ESE into central IL (cirrus clouds more scattered along and north of a Macomb to Bloomington line.

Canadian high pressure to drift across the southern Great Lakes overnight and near the mid Atlantic Coast by sunset Tue. This will continue dry weather over the area through daytime hours on Wed. A weak upper level disturbance to increase mid/high clouds tonight while chances of light rain/sprinkles should be west and sw of IL tonight. Mid to high clouds decrease se of area early Tue morning with partly to mostly sunny skies expected and lighter south to se winds around 10 mph or less. Subfreezing lows overnight in the upper 20s/lower 30s, with highs Tue in the upper 50s to around 60F.

More clouds arrive Tue night and not as cool with lows in the low to mid 40s. Breezy south to SSW winds develop by Wed morning on back side of high pressure ridge off the mid Atlantic Coast. Despite partly to mostly cloudy skies Wed, expect mild highs in the low to mid 70s (upper 70s near the MS river valley of west central IL). A warm front lifting ne over IL by overnight Wed night could bring isolated showers/thunderstorms. About 10 degrees warmer on Thu with near record highs in the low to mid 80s and upper 80s possible sw of Springfield. Strong cold front to push se into central IL late Thu and thru southeast IL during Thu evening. Moderate instability and higher PW ahead of this cold front than the one yesterday could bring more of our area a better chance of strong to potentially severe storms by late Thu afternoon into Thu evening. SPC Day4 has a 15% risk of severe storms across CWA Thu afternoon/evening. Breezy sw winds ahead of cold front Thu to turn north to NE and remain strong during Thu night into Fri, gusting 25-35 mph or higher. Chances of light rain lingers Fri over central and southern CWA especially Fri morning. Much colder highs Fri in the upper 40s to near 50F with subfreezing lows Fri night in the upper 20s to near 30F.

Fair weather returns this weekend as high pressure settles into the area on Saturday. Temperatures warming back up into the lower 60s Sunday and mid to upper 60s next Monday.

The Climate Prediction Center (CPC) 8-14 Day outlook for Mar 31-Apr 6 has 70-80% chance of above normal temperatures over much of IL with precipitation trending 40-50% chance above normal. So the mild and wet/unsettled pattern looks to continue at least into early April.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 620 PM CDT Mon Mar 23 2026

Flight conditions will remain VFR, and light surface winds will gradually veer from northeast to southeast through this TAF period as surface high pressure pushes builds across the regional terminals.

CLIMATE

Issued at 100 PM CDT Mon Mar 23 2026

Records Highs on Thu/Mar 26...

Charleston.... 84 in 1907 Danville...... 78 in 2007 Galesburg..... 83 in 1991 Lincoln....... 79 in 2007 Normal........ 83 in 2007 Olney......... 85 in 1907 Peoria........ 82 in 1907 and 1991 Springfield... 81 in 1991 Urbana........ 81 in 1907

ILX WATCHES/WARNINGS/ADVISORIES

None.