textproduct: Central Illinois

KEY MESSAGES

- Unseasonably warm air (20-25 degrees above normal) arrives this week, peaking Wednesday and Thursday with mid-to-upper 60s temperatures. Gusty southwest winds (30-40 mph) will precede this warmup.

- Several chances for rain and thunderstorms this week. There is a conditional threat for severe weather exists Thursday but is not particularly likely.

DISCUSSION

Issued at 201 AM CST Sun Feb 15 2026

Steady rain has been ongoing for hours now. The rain should start coming to an end here soon as the system exits off to the east this morning. It should be out of southeastern IL by mid morning (13- 15z). Behind the rain, in areas that have already cleared out and have started to see skies clearing as well, some patchy fog is possible as we make our way to sunrise this morning.

Above normal temperatures aren't going anywhere anytime soon. Highs in the upper 50s to mid 60s, and lows in the mid 30s to mid 40s are forecast for the next week. The warmest day being next Wednesday with the NBM having a 50-80% chance of temperatures exceeding 65 degrees that afternoon. Monday through Wednesday, while being warm, will also be quite windy, with forecast wind gusts of 20-30 mph. Pressure gradient will be tightening ahead of a series of low pressure systems this week. The strongest wind gusts (30-40 mph) are expected from Tuesday night into Wednesday afternoon. NBM probabilities are showing a 60-80% chance of wind gusts exceeding 30 mph during that time.

There is a series of low pressure systems forecast to travel across the US this week. The first arriving Tuesday night into Wednesday morning is the next chance (20-40%) for some rain, particularly north of I-70, as a low passes off to the north of IL. Rainfall amounts look to be pretty minimal (< 0.1 inch) as of this forecast cycle.

The second will hold a bit more impact and is expected Thursday into Friday. This system will bring rain and thunderstorm chances (30- 50%) to central and southeastern IL. QPF of up to a quarter of an inch. Thursday afternoon forecast soundings are showing a couple hundred J/kg of MUCAPE and around 30 knots of bulk wind shear. This is stunted although by a cap of up to -100 J/kg of CIN. Machine learning is hinting at the possibility of severe weather with this system, but confidence is very low as of now in any severe weather occuring. Not to say it won't happen, so we will continue to monitor trends as we enter this new week.

A cool down to more seasonable temperatures behind the series of systems mid to late week. Highs next weekend in the mid 30s to mid 40s and lows in the 20s.

Copple

AVIATION

(For the 12z TAFs through 12z Monday Morning) Issued at 526 AM CST Sun Feb 15 2026

LIFR/IFR cigs and IFR/MVFR vis have developed this morning. Ceilings may bounce around a little as the stratus deck breaks up / moves out. The fog should begin to lift by 14z with ceilings scattering out later this morning. Expecting VFR conditions to develop by around 16z-18z and to continue until late in the 12z period. MVFR threshold ceilings move back in by the end of the period.

Copple

ILX WATCHES/WARNINGS/ADVISORIES

None.