textproduct: Central Illinois

KEY MESSAGES

- A period of light freezing rain or sleet is possible (10-25% chance) northeast of a Lacon to Paris line through 9am this morning.

- Northwest winds will gust up to 35 mph beginning mid morning and continuing into the afternoon.

- After a seasonably cold Saturday, temperatures will warm to above normal early next week. On Tuesday, the warmest day, there is a 60-80% chance temperatures climb above 50 degrees.

DISCUSSION

Issued at 159 AM CST Fri Feb 6 2026

***** SLIGHT CHANCE AM MIXED PRECIP, BREEZY TODAY *****

At 2am, a warm front was draped north-south across central IL, with westerly winds advecting a milder airmass into the region from Iowa and Missouri. A positively-tilted shortwave trough was generating snow across east-central and northeast Wisconsin, with a small area of scattered precip (which ASOS/AWOS are reporting as "unknown") further west, in the warm advection wing immediately ahead of the cold front. The southwestern extent of this precip is progged to graze or narrowly miss our northeast counties around sunrise, with HREF generally suggesting the highest chances (20-35%) in northeast IL and west-central IN but the REFS' maximum precip chances (15-25%) along roughly I-74. NAM and RRFS forecast soundings for Danville show a saturated, above-freezing warm nose just a few hundred feet off the surface, while the RAP and HRRR in contrast don't quite depict saturation. In either case, freezing rain/sprinkles would be the most likely p-type, though can't rule out graupel/ice pellets given (1) convective-looking appearance of this upstream activity on radar, (2) lack of low ceilings, and (3) a secondary saturated zone depicted higher-up (and between 0 and -10 degC) on forecast soundings. From roughly 6-9am, we maintain 10-25% chances for both sleet and freezing rain north of a Lacon to Paris line, in line with blended highres (HREF/REFS) guidance. We'll continue to monitor upstream observations for any sign of the more troublesome freezing rain p-type, and will issue a Winter Weather Advisory if necessary for this yet low probability (but potentially high-impact) weather, which could result in a slippery morning commute for some.

Despite the cool advection behind the cold front today, temperatures will remain seasonable with afternoon highs anywhere from the mid 30s to low 40s - warmest in west-central IL. However, northwest winds gusting 30-35 mph will make it feel more like it's in the 20s out there. A sharper drop in temperatures will accompany the secondary cold front late this evening, with temperatures dropping into the single digits in many locations by sunrise tomorrow morning - though fortunately winds will go light by then as surface high pressure settles south into the area.

***** SEASONABLY COLD TOMORROW, TURNING MILD NEXT WEEK *****

HREF/REFS mean 850mb temperatures drop to anywhere from -7 to -11 degC (coldest northeast) over central IL early tomorrow morning, but then begin to slowly warm the region by evening as high pressure shifts east into the Ohio Valley allowing low level return flow. Most locations will top out in the 20s tomorrow, though areas west of I-55 stand a 30-60% chance of hitting 30 with any breaks in cloud cover. As upper level ridging over the Plains expands eastward into the region, temperatures warm on Sunday, especially across west- central IL where forecast highs are in the mid to upper 40s. On Monday, lee cyclogenesis over the High Plains will accompany both a northern and southern stream shortwave trough, with the northern low reaching our area sometime on Tuesday. LREF mean brings 850mb temperatures to 9-10 degC over our area ahead of that low Monday night into Tuesday, and while surface heating will depend on cloud cover NBM brings temperatures solidly into the 50s west of I-55 Monday and area-wide by Tuesday, with even a 30-50% chance of reaching 60 southwest of a Macomb to Lincoln to Effingham line on Tuesday. Behind that low, temperatures will turn cooler for the second half of the work week, with daily highs generally in the upper 30s to mid 40s.

***** SHOWERS MID WEEK *****

The Tuesday system will bring a 40-60% chance for rain, and possibly (10-20% chance) a couple thunderstorms depending on moisture return ahead of the low, which will likely be limited by the southern stream system crossing the Deep South. Still, GEFS and EPS ensemble means bring PWATs to upwards of 0.75", which is above the 90th percentile of raob climatology for February 10th. For what it's worth, NBM/LREF offer around a 10-20% chance for more than a half inch of rain. While this system will bring our best opportunity for rain, one/more additional disturbances could offer additional precip chances later in the week. Due to timing and placement differences among LREF ensemble members, NBM has painted continuous 15-30% PoPs in the forecast Wednesday through Friday.

Bumgardner

AVIATION

(For the 12z TAFs through 12z Saturday Morning) Issued at 541 AM CST Fri Feb 6 2026

A LLJ associated with low pressure moving through the Great Lakes is resulting in LLWS with speeds reaching 40-45 kt at 2kft, as seen on our 12z raob. This should move out of the area as a cold front moves through between 13-15z (7-9am). Winds will veer to northwesterly behind that front and gust over 25 kt at times through much of the afternoon, waning as low stratus dissipates after 22z/4pm. Our forecast relied on GLAMP, which suggests the MVFR ceilings arriving later this morning will depart by 00z, though it's worth noting HREF hangs on to 30-50% probabilities through 03z/9pm at SPI, DEC, and CMI.

Bumgardner

ILX WATCHES/WARNINGS/ADVISORIES

None.