Best time to visit Illinois

Find the best time to visit Illinois and plan your perfect trip in 2024/2025. Get holiday inspiration, weather guides, travel advice and find great deals.

Illinois by month

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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.

All Illinois destinations

When is the best time to visit Illinois?

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

Maximum daytime temperature = 22 - 30°C [remove]

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Max Day Temperature (°C)

  • -1°C maximum daytime temperature in January in Illinois (Chicago)-1
    Jan
  • 1°C maximum daytime temperature in February in Illinois (Chicago)1
    Feb
  • 8°C maximum daytime temperature in March in Illinois (Chicago)8
    Mar
  • 15°C maximum daytime temperature in April in Illinois (Chicago)15
    Apr
  • 21°C maximum daytime temperature in May in Illinois (Chicago)21
    May
  • 27°C maximum daytime temperature in June in Illinois (Chicago)27
    Jun
  • 29°C maximum daytime temperature in July in Illinois (Chicago)29
    Jul
  • 28°C maximum daytime temperature in August in Illinois (Chicago)28
    Aug
  • 24°C maximum daytime temperature in September in Illinois (Chicago)24
    Sep
  • 17°C maximum daytime temperature in October in Illinois (Chicago)17
    Oct
  • 9°C maximum daytime temperature in November in Illinois (Chicago)9
    Nov
  • 2°C maximum daytime temperature in December in Illinois (Chicago)2
    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.

Best time to visit

The weather guide for Illinois (Chicago) shows long term weather averages processed from data supplied by CRU (University of East Anglia) & today's weather forecast provided by meteoblue. Find out more about our data sources.

Metric (°C / mm)  |  Imperial (°F / inches)

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Illinois travel features

Do you want to learn more about Illinois? Read our latest features covering travel tips and insider destination guides on where to go and what to do in Illinois.

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