textproduct: Central Illinois

KEY MESSAGES

- A Red Flag Warning is in effect for most areas near and west of I- 55 this afternoon. Burning is highly discouraged due to breezy southwesterly winds, low relative humidity, and antecedent dry conditions.

- Wintry precip returns Sunday night. Minor snow accumulations are possible, resulting in a 10-30% chance of minor travel impacts.

- A warmer and wetter pattern is expected during the first half of March, which should bring beneficial rainfall to the region.

DISCUSSION

Issued at 116 PM CST Fri Feb 27 2026

A deepening sfc low pressure was located over the Canadian Prairie, due north of the state of IL, with a cold front extending south- southwestward across WI and IA. Ahead of this front, breezy southwest winds across the warm sector gusting around 30 mph have pushed temps into the 60s and even 70s in some spots (Lincoln, Jacksonville, Pittsfield, Quincy) as of 1pm/19z. Relative humidity values are decreasing, and will continue to do so over the next few hours as temps warm/PBL mixing deepens. The forecast is verifying quite well, with the lowest RH values being observed west of I- 55/within the Red Flag Warning area, with values between 25-30% as of 1pm/19z. Burning is strongly discouraged this afternoon. Several hot spots have already been noted in satellite imagery.

The cold front will push in late this evening, swinging winds to east-northeasterly by Sat AM. That front pushes south of the CWA, but as a weak sfc low tracks into MO during the day Sat it will lift back north. Low-level WAA could spawn a few light showers during the late afternoon/evening, but fcst soundings are quite dry in the low levels. The latest blended guidance lowered PoPs (less than 15%), and that seems reasonable given the low-level dry air. Can't rule out sprinkles or pockets of very light rain during the late afternoon/evening (mainly south of I-72), but most areas will be dry for the majority of the day. Given that aforementioned frontal boundary, a north-south gradient in temps is expected, with highs ranging from the mid/upper 40s to low 60s. Models vary on the frontal placement, impacting how much of the area actually sees temps reach the 50s. The probabilistic NBM has a 90% chance of highs in the 50s south of I-72, decreasing to less than a 50% chance north of a Canton to Bloomington line.

*** WINTRY PRECIP RETURNS ***

Models continue to show a disturbance moving through late in the weekend, bringing a potential for modest snow accumulations. Synoptically, the sfc pattern in advance of this system will be characterized by a strong, expansive sfc high centered over the eastern Great Lakes and a sfc frontal boundary positioned well south of the ILX CWA. The greatest points of uncertainty with this system are 1) where or if any icy precip types will occur and 2) the potential for a tight northern gradient in snowfall as the sfc high funnels dry low-level air in from the northeast. Guidance is also trending slower with the precip onset, keeping the ILX forecast area dry through most of the afternoon Sunday, with precip moving in from the west Sunday evening.

Latest ensemble guidance trended lower with the QPF amounts. There is still a 40-60% chance of at least 1" of snow along/north of Jacksonville-to Paris line, but the probability of 4" of snow drops below 25%. It's worth noting that given the expected tight gradient in snow along the north side of this system that some models have no snow at all for the I-74 corridor. Several days ago, the concern with this system was the potential for a prolonged setup conducive to freezing rain. Those concerns have since abated. Fcst soundings generally show the low-level warm nose remaining below freezing, but there are still times where there is a layer aloft near freezing. This suggests that brief periods of sleet or freezing rain can't be ruled out, but most of the precip should be rain or snow in our forecast area. The probability of minor travel impacts is down to 10- 30%, which is a significant decrease from several days ago when the forecast values were closer to 60-70%.

In advance of our next system, models show a wing of WAA-driven precip developing and overspreading the area either Monday afternoon (less likely) or Monday night (more likely). That low-level WAA will drive the warm nose above freezing, so will need to keep an eye on sfc temps to ensure they are also above freezing, which is what most guidance shows at this time (suggests rain, not freezing rain).

*** TRENDING WETTER ***

No big chances noted in the extended forecast at this time, as there remains broad ensemble support for a warmer and wetter pattern through the first half of March. As noted yesterday, AI- based ensemble guidance continues to highlight a narrower corridor where total precip amounts have a strong chance (>80%) of exceeding 2" through March 11. These AI-based ensembles focus the greatest probs south of I-72, whereas the traditional ensembles have a much broader swath that encompasses most of the ILX CWA.

There are differences in exact timing and frontal placement, but current deterministic models show a trough ejecting from the Four Corners region Tues into Wed, while a stalled frontal boundary is draped east-west somewhere near or across the ILX CWA. With a sfc high pressure off the eastern seaboard and a developing sfc low over the Plains, this will funnel gulf moisture toward the stalled frontal boundary and should produce the first of several periods of rain/storms locally. Timing differences become more stark towards the middle/latter half of next week, but rain chances will persist as that trough/associated sfc low lift towards the area. All told, the latest NBM probability of at least 1" of rain through next Friday morning is 60-80%. Given the ongoing drought, streamflows across the area are well-below normal, and little to no frost depth expected as we enter this warmer/wetter pattern, the flooding concerns appear muted, at least through next week.

It's too early to determine specific windows of severe storm potential, beyond acknowledging that this is indeed a favorable synoptic pattern for occasional strong/severe storms.

Erwin

AVIATION

(For the 18z TAFs through 18z Saturday Afternoon) Issued at 1100 AM CST Fri Feb 27 2026

VFR conditions prevail through the period. Breezy southwest winds will gust up to 25-30 kts this afternoon. Mostly clear skies are expected through today, then a scattered mid/upper level deck moves in overnight or early Sat AM. The gusts will diminish after 00z, and wind direction will steadily pivot from southwest to northerly overnight, then to easterly or east-southeasterly by the end of the period.

Erwin

ILX WATCHES/WARNINGS/ADVISORIES

Red Flag Warning until 6 PM CST this evening for ILZ027>031-036- 037-040>042-047>051.