Which is the hottest month in Decatur?

The hottest time of year in Decatur is normally July. Expect maximum daytime temperatures to reach 31°C with high heat and humidity.

Which month has the most rain in Decatur?

In terms of rainfall, July is usually the wettest month in Decatur with 107mm on average. There are normally 9 days in July with some rain.

When is it sunniest in Decatur?

The sunniest time of year in Decatur is normally July with bright sunshine on average for 70% of daylight hours; that's 10 hours of sunshine per day.

Best time to visit Decatur

Q: When is the best time to visit Decatur?

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

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Decatur by month

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

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Destination

When is the best time to visit Decatur?

The best time to visit Decatur is May based on the following average weather conditions.

Maximum daytime temperature = 72 - 86°F [remove]
Daily hours of sunshine = 10 hours or more [remove]

Change the criteria to reflect your weather preferences.

1
Jan
1
Feb
1.5
Mar
3
Apr
4.5
May
4.5
Jun
4
Jul
4
Aug
4
Sep
3.5
Oct
0.5
Nov
0.5
Dec

Change criteria

Max Day Temperature (°F)

34
Jan
39
Feb
52
Mar
64
Apr
75
May
84
Jun
88
Jul
84
Aug
79
Sep
68
Oct
52
Nov
37
Dec

Hours of Sunshine (daily)

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

Best time to visit

Destination

Daytime temperature

Sunshine hours

Sea temperature

Monthly rainfall

Days with some rain

Heat & humidity

The weather guide for Illinois (Decatur) 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) | Imperial (°F)