Best time to visit Illinois

Q: When is the best time to visit Illinois?

The best time to visit Illinois (Chicago) is June based on the following average weather conditions. Maximum daytime temperature = 22 - 30°C. Daily hours of sunshine = 10 hours or more.

Q: Which is the hottest month in Illinois?

The hottest time of year in Chicago, Illinois is normally July. Expect maximum daytime temperatures to reach 29°C with moderate heat and humidity.

Q: Which month has the most rain in Illinois?

In terms of rainfall, July is usually the wettest month in Chicago, Illinois with 100mm on average. There are normally 10 days in July with some rain.

Q: When is it sunniest in Illinois?

The sunniest time of year in Chicago, Illinois is normally July with bright sunshine on average for 69% of daylight hours; that's 10 hours of sunshine per day.

Q: When is the sea warmest in Illinois?

The sea is usually at its warmest in Chicago, Illinois in August when the water temperature reaches 21°C.

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Illinois by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

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Destination

Top Illinois destinations

Below are the temperatures expected today at popular countries, regions and places in Illinois. Select a destination to compare today's forecast with average weather conditions.

30
Chicago
30
Springfield

All Illinois destinations

When is the best time to visit Illinois?

The best time to visit Illinois (Chicago) is June based on the following average weather conditions.

Maximum daytime temperature = 22 - 30°C [remove]
Daily hours of sunshine = 10 hours or more [remove]

Change the criteria to reflect your weather preferences.

0.5
Jan
1
Feb
1.5
Mar
1.5
Apr
4
May
5
Jun
4.5
Jul
4.5
Aug
4
Sep
1.5
Oct
0.5
Nov
0
Dec

Change criteria

Max Day Temperature (°C)

-1
Jan
1
Feb
8
Mar
15
Apr
21
May
27
Jun
29
Jul
28
Aug
24
Sep
17
Oct
9
Nov
2
Dec

Hours of Sunshine (daily)

4
Jan
5
Feb
6
Mar
7
Apr
9
May
10
Jun
10
Jul
9
Aug
8
Sep
6
Oct
4
Nov
3
Dec

Which is the hottest month in Illinois?

The hottest time of year in Chicago, Illinois is normally July. Expect maximum daytime temperatures to reach 29°C with moderate heat and humidity.

Which month has the most rain in Illinois?

In terms of rainfall, July is usually the wettest month in Chicago, Illinois with 100mm on average. There are normally 10 days in July with some rain.

When is it sunniest in Illinois?

The sunniest time of year in Chicago, Illinois is normally July with bright sunshine on average for 69% of daylight hours; that's 10 hours of sunshine per day.

When is the sea warmest in Illinois?

The sea is usually at its warmest in Chicago, Illinois in August when the water temperature reaches 21°C.