United States · 1991–2020

Best time to visit
Chicago.

September leads for comfortable weather in Chicago: typically 24.8°C by day, 15.1°C at night, with 68 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortSeptember

Typical high24.8°C

Typical low15.1°C

Rain in September68 mm

Comfort

September

September · June · May

89climate match

Beach

July

July · August · June

82climate match

Outdoors

October

October · May · September

72climate match

The weakest month is January, scoring 5 against September’s 89 — days reach only 0.5°C, 23° below the 24°C the score treats as ideal.

Month by month

The whole year,
without the guesswork.

The bars show the comfort score. Day and night temperatures come from daily observed highs and lows; rain is the historical monthly estimate.

Jan

50.5° / -6.8°

Feb

52.6° / -5.3°

Mar

168.7° / -0.1°

Apr

4115.6° / 5.3°

May

6821.6° / 11.1°

Jun

7127° / 16.9°

Jul

6229.4° / 20°

Aug

6528.1° / 19.2°

Sep

8924.8° / 15.1°

Oct

5317.4° / 8.1°

Nov

249.9° / 2°

Dec

53° / -4°

Monthly climate evidence for Chicago — daylight is calculated from latitude, everything else is measured, sea temperature from the nearest open water 4 km away
Month	Day	Night	Rain	Wet days	Sea	Daylight	Comfort	Coverage
January	0.5°C	-6.8°C	37 mm	5.5	3.3°C	9 h 27	5	Good coverage
February	2.6°C	-5.3°C	38 mm	6	2.0°C	10 h 31	5	Good coverage
March	8.7°C	-0.1°C	52 mm	7.3	2.0°C	11 h 48	16	Good coverage
April	15.6°C	5.3°C	92 mm	9.2	3.8°C	13 h 17	41	Good coverage
May	21.6°C	11.1°C	111 mm	10.3	7.1°C	14 h 31	68	Good coverage
June	27°C	16.9°C	103 mm	9.6	14.1°C	15 h 12	71	Good coverage
July	29.4°C	20°C	87 mm	7.1	20.9°C	14 h 56	62	Good coverage
August	28.1°C	19.2°C	104 mm	8.2	22.5°C	13 h 52	65	Good coverage
September	24.8°C	15.1°C	68 mm	6.7	20.1°C	12 h 26	89	Good coverage
October	17.4°C	8.1°C	92 mm	8.6	14.5°C	11 h 00	53	Good coverage
November	9.9°C	2°C	54 mm	6.5	9.2°C	9 h 46	24	Good coverage
December	3°C	-4°C	49 mm	6.7	5.6°C	9 h 09	5	Good coverage

Records at CHICAGO MIDWAY AP, 1997–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	18.3°C7 Jan 2008	-29.9°C30 Jan 2019	52 mm8 Jan 2026	79 mm2005 · driest 5 mm in 2004	29
February	23.3°C27 Feb 2024	-22.7°C5 Feb 2007	59 mm20 Feb 2018	112 mm2018 · driest 3 mm in 2003	29
March	30.0°C21 Mar 2012	-20.0°C4 Mar 2002	51 mm30 Mar 2017	143 mm2009 · driest 12 mm in 2015	29
April	31.7°C18 Apr 2002	-6.0°C7 Apr 2018	50 mm29 Apr 2020	163 mm2013 · driest 32 mm in 2005	29
May	36.1°C27 May 2012	-0.5°C9 May 2020	93 mm17 May 2020	194 mm2020 · driest 15 mm in 2023	30
June	38.3°C21 Jun 2022	3.9°C1 Jun 2003	60 mm21 Jun 2018	195 mm2010 · driest 26 mm in 2012	30
July	40.0°C24 Jul 2005	12.2°C10 Jul 1997	120 mm24 Jul 2010	287 mm2023 · driest 21 mm in 2011	30
August	37.8°C24 Aug 2023	9.4°C31 Aug 2009	93 mm26 Aug 2012	237 mm2014 · driest 18 mm in 2008	29
September	35.6°C10 Sep 2013	5.6°C29 Sep 2003	80 mm18 Sep 2015	236 mm2008 · driest 14 mm in 2017	29
October	32.2°C3 Oct 2025	-3.2°C31 Oct 2019	132 mm14 Oct 2017	263 mm2017 · driest 24 mm in 1999	29
November	25.0°C1 Nov 2016	-12.7°C12 Nov 2019	45 mm18 Nov 2003	144 mm2003 · driest 15 mm in 1999	29
December	22.2°C3 Dec 2012	-22.7°C23 Dec 2022	46 mm28 Dec 2015	137 mm2015 · driest 4 mm in 2017	29

Typical days per month at CHICAGO MIDWAY AP, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)	Snow days
January	0	0	27	1	1
February	0	0	23	1	<1
March	<1	0	18	2	1
April	3	<1	3	3	0
May	10	3	0	4	0
June	21	9	0	3	0
July	28	15	0	3	0
August	26	10	0	4	0
September	15	5	0	2	0
October	4	<1	<1	3	0
November	<1	0	11	2	<1
December	0	0	24	1	2

How often, not how much — every day in CHICAGO MIDWAY AP’s record sorted by what it was actually like, rather than averaged
Month	Warm & dry days	Wet days	Washouts	Week with 3+ wet days	Daytime mean has ranged
January	0%	18%	4%	17%	-2.0–3.3°C
February	<1%	20%	3%	16%	-2.3–7.0°C
March	6%	25%	6%	33%	6.4–13.0°C
April	20%	32%	10%	41%	14.0–17.8°C
May	45%	32%	11%	40%	18.9–24.4°C
June	66%	31%	12%	37%	25.6–29.2°C
July	76%	24%	10%	25%	27.5–31.1°C
August	74%	26%	11%	27%	26.7–29.5°C
September	69%	21%	7%	23%	23.0–26.9°C
October	27%	27%	10%	30%	15.9–19.7°C
November	6%	21%	6%	20%	6.3–13.3°C
December	<1%	21%	5%	18%	-0.2–6.7°C

A warm and dry day reaches 20°C with under 1 mm of rain; a wet day gets 1 mm or more; a washout gets 10 mm or more. The week column is the share of seven-day stretches in that month, across the station’s whole daily record, that contained three or more wet days — the odds a week-long trip is rained on repeatedly, counted rather than modelled. The last column is the 10th to 90th percentile of that month’s daytime average across individual years: a narrow band means the average is what you will get, a wide one means the average is a midpoint between years that felt quite different.

1998Each stripe is one year’s mean temperature against the 28-year average. Warmest: 2024. Coolest: 2014.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 4887398
NOAA station: USW00014819 · CHICAGO MIDWAY AP
Station distance: 11.4 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 22 usable years
Daylight: Calculated from latitude 41.85°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Sea temperature: NOAA OISST v2.1 1991–2020 monthly climatology, nearest open water 4 km from the place centre. A sheltered bay can run warmer than the open sea it is measured from.
Important limit: Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.

These places read the same station, so their numbers are identical — distance from CHICAGO MIDWAY AP is what differs

West Town→Near North Side→Cicero→South Lawndale→Logan Square→Lincoln Park→

Or put two places side by side: Chicago vs West Town

Best time to visitChicago.