textproduct: Central Illinois

KEY MESSAGES

- A fast-moving disturbance will bring a period of light snow tonight. Snowfall will generally be 1 inch or less: however, there is a 60-70% chance that a few locations along and northeast of a Lacon to Champaign line will exceed 1 inch.

- Cold January weather will prevail Saturday through Tuesday. High temperatures during that period will only reach the teens and lower 20s while overnight lows dip into the single digits.

LONG TERM

(Saturday through Wednesday) Issued at 242 AM CST Thu Jan 15 2026

As the Ontario low drops into the Great Lakes, it will drag a cold front southward through central Illinois Friday night. Enough lift will be generated along/near the boundary to trigger scattered snow showers as it passes. A couple tenths of an inch of snow will be possible.

The main weather story in the extended will be the colder conditions expected this weekend into early next week. Saturday will be a blustery and cold day with scattered snow flurries and highs only in the teens and lower 20s. Sunday will be about the same, although forecast soundings suggest partial sunshine and lighter winds. Yet another short-wave trough digging southward out of Canada will send a re-inforcing shot of very cold air into the region late Sunday night into Monday. Highs on Monday will struggle to climb into the teens while overnight lows dip into the single digits. After that, a slow moderation is expected as highs climb back to near seasonal normals in the middle 30s by next Wednesday.

Barnes

AVIATION

(For the 12z TAFs through 12z Friday Morning) Issued at 538 AM CST Thu Jan 15 2026

Skies are clear across much of central Illinois early this morning: however, a lake-enhanced band of low clouds has streamed southward along/east of a KPNT...to KBMI...to KDEC line. Based on satellite trends, it appears KCMI will maintain MVFR ceilings through around 15z. Further west, opted to include a TEMPO group for MVFR at KBMI through 14z and just mentioned SCT MVFR at KDEC. Once the band dissipates, mid/high clouds will increase from the west this afternoon as a trough axis approaches. Light snow will develop ahead of the trough along the Mississippi River after 21z/3pm...then will spread across the central Illinois terminals this evening. Based on the latest HRRR/RAP output, have introduced MVFR ceilings and light snow at KPIA by 01z...then further east to KCMI by 03z. The snow band will quickly shift eastward into Indiana, followed by just a few flurries overnight. Confidence in the ceiling forecast once the band departs is poor as model solutions vary. The HRRR/RAP indicates VFR, while NAM forecast soundings suggest continued MVFR even after the snow stops. At this point, have opted to scatter the lowest cloud deck and go with a low VFR ceiling after midnight. Winds will initially be NW at around 10kt early this morning, then will back to SW this afternoon. The SW winds will increase to 10-15kt tonight as the trough swings through the region.

Barnes

ILX WATCHES/WARNINGS/ADVISORIES

None.