Illinois
When to go?
Mean −3 °C, 7 rain days in the month (60 mm).
Against
- Freezinglows of −7 °C
Mean 0 °C, 7 rain days in the month (58 mm).
Against
- Freezinglows of −5 °C
Mean 6 °C, 9 rain days in the month (81 mm).
Nothing against it.
Mean 12 °C, 10 rain days in the month (108 mm).
Nothing against it.
Mean 18 °C, 11 rain days in the month (124 mm).
Nothing against it.
Mean 23 °C, 8 rain days in the month (119 mm).
Good for
- Ideal to visitTemperature and rain in the ideal range.
Mean 25 °C, 7 rain days in the month (107 mm).
Against
- Hothighs of 30 °C
Mean 24 °C, 7 rain days in the month (92 mm).
Good for
- Ideal to visitTemperature and rain in the ideal range.
Mean 20 °C, 6 rain days in the month (82 mm).
Good for
- Ideal to visitTemperature and rain in the ideal range.
Mean 13 °C, 7 rain days in the month (83 mm).
Nothing against it.
Mean 6 °C, 7 rain days in the month (69 mm).
Nothing against it.
Mean 0 °C, 8 rain days in the month (64 mm).
Against
- Freezinglows of −4 °C
The best months are June, August–September. Avoid December–February (freezing), July (hot).
Climate zones
- Freezing, dry
- Freezing
- Freezing, wet
- Cold, dry
- Cold
- Cold, wet
- Mild, dry
- Mild
- Mild, wet
- Hot, arid
- Hot
- Hot, wet
- Torrid, arid
- Torrid
- Torrid, wet
Mean maximum and minimum temperature and mean monthly precipitation of the season (the mean of its three months), ERA5-Land 1996–2025, at about 9 km resolution: colours are in levels (the same as the city scale) and smaller details are not real.
What is the climate like?
Area mean indicative, over the whole territory
Temperature and rain
Monthly min and max temperature (°C)
Monthly min and max temperature (°C)
How much it rains
Rain days and how much water
Rain days and how much water
Bars: length = rain days, thickness = mm on a rain day, area = the month's rain. 3 mm a day7 mm a day15 mm a day
Colour = the month's rain: 103060100160250400mm
Daylight hours
Mean daylight hours over the whole territory.
Snow on the ground
Mean snow depth on the ground (cm)
Mean snow depth on the ground (cm)
Spatial mean over the whole area, weighted by area (cosine of the latitude), not by population: indicative only, since the climate varies a lot within an area (coasts, plains, mountains). Look at the cities for the weather you will find.