What is the hottest month in Chicago?

July — average highs around 82° with lows near 67°.

What is the coldest month in Chicago?

January, when nights typically drop to 20° and days top out near 33°.

What is the rainiest month in Chicago?

July, averaging about 5.8 in of precipitation; the driest is November at roughly 2.3 in.

How warm is Chicago over the year?

The annual mean is 52°, with about 46 in of precipitation in a typical year (1991-2020 normals).

Chicago Climate — Monthly Normals 1991-2020

Climate in Chicago

The typical year in Chicago (Illinois), from 1991-2020 normals. For what's happening now, see the current forecast; a month ahead — the 30-day outlook.

Annual mean temp

11°C

average across 12 months

Annual precipitation

1156 mm

yearly total

Warmest month

Jul

⌀ max 27°C

Coldest month

Jan

⌀ min -6°C

Temperatures by month

typical high (orange) · typical low (blue)

Jan

-7° … 0°

Feb

-6° … 2°

Mar

0° … 9°

Apr

4° … 14°

May

11° … 20°

Jun

17° … 26°

Jul

20° … 28°

Aug

19° … 27°

Sep

16° … 24°

Oct

9° … 17°

Nov

2° … 9°

Dec

-2° … 4°

Precipitation by month

monthly totals across the year

Jan

67 mm

Feb

60 mm

Mar

85 mm

Apr

94 mm

May

131 mm

Jun

123 mm

Jul

147 mm

Aug

104 mm

Sep

102 mm

Oct

119 mm

Nov

58 mm

Dec

66 mm

The short version

RegionIllinois

Latitude41.8500°N

Annual mean11°C

Annual precipitation1156 mm

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Weather map — Chicago

Chicago →

Source · 1991-2020 normals

Chicago, IL Climate