Bundle up because a cold front is arriving on Friday, according to the National Weather Service. Expect the lowest temperatures since March inland and single-digit wind chills lakeside.
Lake effect snow is predicted for the early afternoon on Friday, which occurs when cooler atmospheric conditions cause a cold air mass to move over Lake Michigan, turning water vapor into snow along the lakeshore. Precipitation may be light, but the National Weather Service puts all of Chicagoland in its threat area.
With flurries possible, tomorrow's snow would be slightly earlier than the average first measurable snowfall, which typically falls on November 16. Technically, the snow would only qualify as measurable if there's more than one-tenth of an inch on the ground at the measuring station near O'Hare International Airport. Historically, the city's first measurable snowfall is heavy—remember last year on December 4 when 6.4 inches fell on Chicago?
It will be warmest around noon and COLD for the remainder of the day, so brace yourself for a brutal commute home.