A late-season snow system may make its way into the area Monday night into Tuesday when temperatures will dip below freezing and frost moves in, forecasters warned.
The change starts with an elevated frost risk and possibly light rain or snow expected overnight Monday night, as temperatures were expected to drop to 31 to 38 degrees, according to the National Weather Service.
With the plummeting temperatures combined with light winds, the frost will develop for north central and northeastern Illinois and northwest Indiana.
On Tuesday, snow is likely, possibly mixed with rain, according to the NWS. It will be mostly cloudy, with a high only near 39 and the chance of precipitation at 70%. This late-season snow system comes complete with wet snow, with accumulations mostly on nonpaved surfaces, officials said.
On Tuesday night, snow should end by 10 p.m., but temperatures will get even colder, from 27 to 34 degrees, causing a significant freeze risk.
It will warm up Wednesday through Saturday, with temperatures expected to range from the 40s to the upper 50s, the weather service said.
As of early Saturday evening, the temperature at O’Hare International Airport was 55 degrees.