Chicago, IL Climate & Monthly Averages
The climate of Chicago
Weather in Chicago is shaped by its humid continental climate - expect warm summers and cold, often snowy winters. July afternoons typically reach 80°F (27°C), while January highs hover near 32°F (0°C). Annual precipitation averages 46.3 inches (1177 mm) over about 132 rainy days.
Climate quick facts
- Hottest month: July - highs near 80°F (27°C)
- Coldest month: January - highs near 32°F (0°C)
- Record high: 99°F (37°C) · Record low: -26°F (-32°C) (2015–2024)
- Wettest month: July (12 rainy days) · Sunniest: July (11.8 h sun/day)
- Climate type: humid continental - warm summers and cold, often snowy winters
- Snow: about 18 days a year
Temperatures through the year
The warmest stretch of the year centers on July. Highs average 80°F (27°C) and overnight lows stay near 67°F (19°C). The coolest month is January, with typical highs of 32°F (0°C) and lows around 20°F (-6°C). Based on 2015–2024 weather data, temperatures have reached as high as 99°F (37°C) and dropped as low as -26°F (-32°C).
Rain, sun and snow
July is usually the wettest month. It brings about 6.0 inches (152 mm) of rain over 12 days, while February is the driest. July brings the most sunshine, averaging 11.8 hours of sun a day. Snow falls on about 18 days in a typical year, mostly from November through April.
Monthly climate table
| Month | High | Low | Rain days | Precipitation | Sunshine | Humidity |
|---|---|---|---|---|---|---|
| January | 32° | 20° | 10 | 2.6 in | 4.9 h/day | 76% |
| February | 36° | 20° | 9 | 2.4 in | 6.8 h/day | 73% |
| March | 45° | 31° | 11 | 3.5 in | 7.9 h/day | 74% |
| April | 54° | 39° | 14 | 4.2 in | 8.8 h/day | 73% |
| May | 66° | 50° | 13 | 5.3 in | 10.1 h/day | 76% |
| June | 77° | 61° | 12 | 4.5 in | 11.6 h/day | 73% |
| July | 80° | 67° | 12 | 6.0 in | 11.8 h/day | 77% |
| August | 80° | 66° | 12 | 4.2 in | 11.5 h/day | 76% |
| September | 75° | 62° | 10 | 3.8 in | 9.6 h/day | 74% |
| October | 62° | 49° | 12 | 4.8 in | 7.5 h/day | 72% |
| November | 48° | 36° | 8 | 2.5 in | 6.0 h/day | 73% |
| December | 39° | 28° | 9 | 2.6 in | 5.0 h/day | 75% |
Chicago month by month
Chicago weather in January
January brings highs around 32°F (0°C), lows near 20°F (-6°C), about 10 wet days and roughly 6 snowy days - typically the coldest month of the year in Chicago.
Chicago weather in February
February brings highs around 36°F (2°C), lows near 20°F (-6°C), about 9 wet days and roughly 4 snowy days - typically the driest month of the year in Chicago.
Chicago weather in March
March brings highs around 45°F (7°C), lows near 31°F (-1°C), about 11 wet days and roughly 2 snowy days.
Chicago weather in April
April brings highs around 54°F (12°C), lows near 39°F (4°C), about 14 wet days and roughly 2 snowy days.
Chicago weather in May
May brings highs around 66°F (19°C), lows near 50°F (10°C), about 13 wet days.
Chicago weather in June
June brings highs around 77°F (25°C), lows near 61°F (16°C), about 12 wet days.
Chicago weather in July
July brings highs around 80°F (27°C), lows near 67°F (19°C), about 12 wet days - typically the hottest month and the wettest month and the sunniest month of the year in Chicago.
Chicago weather in August
August brings highs around 80°F (26°C), lows near 66°F (19°C), about 12 wet days.
Chicago weather in September
September brings highs around 75°F (24°C), lows near 62°F (16°C), about 10 wet days.
Chicago weather in October
October brings highs around 62°F (17°C), lows near 49°F (9°C), about 12 wet days.
Chicago weather in November
November brings highs around 48°F (9°C), lows near 36°F (2°C), about 8 wet days and roughly 1 snowy days.
Chicago weather in December
December brings highs around 39°F (4°C), lows near 28°F (-2°C), about 9 wet days and roughly 3 snowy days.
Seasons in Chicago
Spring (March through May)
Spring in Chicago stays on the cool side of mild, with daytime highs averaging 55°F (13°C) and nights around 40°F (5°C); expect showers on roughly 38 days across the season, plus around 4 snowy days.
Summer (June through August)
Summer in Chicago brings comfortable warmth, with daytime highs averaging 79°F (26°C) and nights around 65°F (18°C); expect showers on roughly 36 days across the season.
Fall (September through November)
Fall in Chicago stays on the cool side of mild, with daytime highs averaging 62°F (16°C) and nights around 49°F (9°C); expect showers on roughly 30 days across the season.
Winter (December through February)
Winter in Chicago is frigid, with daytime highs averaging 36°F (2°C) and nights around 23°F (-5°C); expect showers on roughly 28 days across the season, plus around 13 snowy days. Wind makes those temperatures feel harsher than they sound - pair the forecast winds with the wind speed converter to judge conditions on exposed skin.
Climate questions, answered
What is the average temperature in Chicago?
Is Chicago hot in summer?
Is Chicago cold in winter?
How many rainy days does Chicago get in a year?
Best time to visit Chicago
The best time to visit Chicago is generally May to October, when this window offers the warmest, brightest days of the year. Daytime temperatures in that window typically sit near 73°F (23°C).
Pack for Chicago with a heavy insulated coat, hat and gloves for winter; a compact umbrella or rain shell - showers are a regular feature. Evenings can feel noticeably cooler than afternoons - July nights average 67°F (19°C).
Chicago temperature records (2015-2024)
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.