• 7 DAY OUTLOOK: A brief blast of cold Canadian air moves in for the next few days. Colder tomorrow with our first widespread frost/freeze of the season. Freeze Warning 12 midnight to 9 AM on Monday. Highs will struggle to get into the low 40s. Our first 20s of the season arrive on Tuesday morning and will struggle to get to 40 in the afternoon.
  • A weak weather system drops over us on Tuesday as well. Delivering some snow showers for about 20% of Chicagoland. None is expected to really stick around as thee ground is still pretty warm this time of year. Our first snowfall does usually happen on average by October 31st– but fact that still is of little comfort trick or treaters who have to bundle up. We’re back to seasonal temps by the end of the week—warming about 5-7 degrees each day.
  • WGN Weekly Climate Report: Some weather whiplash underway for Chicagoland. We tied a record high temp at O’Hare of 83 degrees on Tuesday. The old record was set in 1963. But now our first widespread frost/freeze of the season is only hours away and our first chance at some snow is on Tuesday when high temps might only get to 39 degrees.
  • Typically our first snowfall of the year is on October 31st. Though the earliest ever snowfall was on September 25th. The earliest measurable snowfall is October 12th for Chicago. Already there’s snow on the ground not too far from the Windy City already — some even falling in far NW Illinois and southern Wisconsin today.
  • Here’s the setup for upcoming snowfall: cold air moves in Monday and Tuesday. A weak weather system drops down from western Ontario on Tuesday delivering some on/off snow showers in the morning and then rain/snow showers in the afternoon for about 20-30% of the area. Trick or treat time looks blustery, chilly and raw — so a warm component to costumes is a very good idea this year.
  • We’ll likely end the month with some below normal rainfall — despite seeing more than two weeks with measurable precipitation this month. Right now our rainfall totals are more than 2 inches at O’Hare.
  • Lake water temps remain solidly in the mid 50s in Lake Michigan and much of the Great Lakes seeing pretty similar temperature profiles. That keep lakeside areas warmer with our chilly days ahead as we get into November.

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