Will I be hot?
Will I be hot in Chicago in October?
Verdict
No — No, comfortable.
Highs cap at 62°F — no heat-management gear needed.
Day vs. night
Day
62°F
Comfortable
A T-shirt and a light overshirt is enough.
Night
46°F
Cool
You'll want a warm layer after sunset — not a heavy coat.
Why
Chicago in October averages highs of 62°F, lows of 46°F, 9 rainy days.
Temperature is comfortable across the day; pack for style and weather resistance, not heat management.