‘Well below zero’: Freezing temperatures expected overnight Monday into Tuesday

Freezing temperatures are expected through the week with the thermometer reaching “well below zero” overnight Monday into Tuesday, the National Weather Service forecasted Monday.

Much of northern Illinois – including McHenry, Lake, Ogle, Lee, DeKalb, Kane, DuPage, La Salle, Kendall, Grundy, Cook and Will counties – remains under a hazardous weather outlook that warns of an elevated risk for excessive cold.

Temperatures are expected to be particularly frigid where several inches of snow fell over the weekend, according to the outlook.

The National Weather Service forecasts the coldest temperatures overnight for western DeKalb County and eastern Lee and Ogle counties at negative 15 to 17 degrees. Much of the rest of DeKalb, Ogle and Lee, as well as Lake, McHenry and Kane counties are expected to see negative 10 to 15 degrees.

Temperatures will be warmer farther south with negative 5 to 10 predicted for Kendall and northern La Salle counties and negative 5 to zero degrees for southern La Salle, Grundy and Will counties.

Temperatures are expected to warm slightly Wednesday and Thursday before “a reinforcing shot of cold air arrives” Thursday night, the National Weather Service said on Twitter.