textproduct: Chicago

KEY MESSAGES

- Chance of snow tonight with less than an inch of accumulation mainly south of a Peru, IL to Lafayette, IN line.

- Brief warm for the end of the week, then colder with some additional snow chances over the weekend and into early next week.

DISCUSSION

Issued at 121 PM CST Wed Feb 25 2026

Temperatures this afternoon remain in the 30s. Winds are out of the northwest and slightly breezy with gusts around 20 mph. Other than those chillier temperatures, it has been quite a beautiful day. However, satellite imagery shows cloud cover associated with an upper level trough over the northern Plains that is dropping southeastward. In addition to an increase in cloud cover across the region, this system will provide the next chance for accumulating snow for central Illinois. Models continue to keep the track of the surface low well to the south of our area. The best chance for snow remain south of a Peru, Illinois to Lafayette, Indiana line, but accumulations should be less than an inch. A flurry north of that line cannot be completely ruled out, but confidence remains low.

Surface high pressure will grow locally Thursday as an upper level trough moves over central Canada Friday into Saturday. Winds will turn southerly and usher in milder temperatures tomorrow, with a chance for highs to touch the low 60s on Friday (about 20 degrees above normal!). As the Canadian trough strengthens on Friday, the pressure gradient response over the region will tighten and allow for breezier conditions to develop with wind gusts 25 to 30 mph expected.

A cold front associated with the Canadian trough will move over the forecast area Friday night through Saturday morning. NBM PoPs remain in the 20 to 40 percent range and given how far away the area is from the better forcing, these PoPs seemed reasonable. While there is a chance of snow, the lack of QPF with this system and drier air near the surface trends toward minimal accumulations, with the better chances north of Interstate 88. As the baroclinic zone gets hung up over central Illinois, a sharp temperature gradient is expected with mid to upper 40s south of Interstate 80 and mid to upper 30s to the north.

Persistent northwest flow behind the front will return chillier temperatures to the area through early next week. Highs on Sunday and Monday are expected in the 30s with morning lows in the teens to mid 20s. Another synoptic system is expected to drop out of Canada on Sunday and pass over Illinois Sunday night into Monday. While this system does look like it could produce accumulating snow, models are consistently trending the track just south of our forecast area. There is still a lot of discrepancies in the ensembles, but it looks like the best chances for snow are south of Interstate 80.

The pattern next week looks somewhat active as models are trying to resolve another upper level trough to pass over the area on Tuesday and maybe another late in the week. With winds potentially turning to the south on Tuesday, it would allow for better warm air advection out ahead of it. This could lead to chances for rain versus snow, but it is too early to say. But the extended models do appear to be favoring a gradual warming trend through the end of next week.

DK

AVIATION /00Z TAFS THROUGH 06Z FRIDAY/

Issued at 521 PM CST Wed Feb 25 2026

There are no forecast concerns this period. Northwest winds under 10kt this evening will become light and variable overnight and then become southerly mid/late Thursday morning. Speeds will increase into the 10-12kt range during the afternoon with some higher gusts possible. Speeds will diminish under 10kts with sunset Thursday evening. cms

LOT WATCHES/WARNINGS/ADVISORIES

IL...None. IN...None. LM...None.