Decatur Weather in August

What's the weather like in Decatur (Illinois) in August 2024?

The climate in Decatur during August can be summarized as hot, humid and a little damp.

August is in the summer in Decatur and is typically the 2nd warmest month of the year. Daytime maximum temperatures average around a muggy 30°C (85°F), whilst at night 17°C (62°F) is normal.

Decatur weather averages (imperial / metric)
Daytime temperature 29.5°C 85.1°F
Nightly temperature 16.7°C 62.1°F
Average temperature 23.1°C 73.6°F
Daily sunshine 10 hrs
Avg rainfall 93 mm 3.7 ins
Rainy days 8 days
Sea temperature 22.4°C 72.3°F
Humidity 74%
Windspeed 13kph 8 mph

On average August is the 5th wettest month of the year in Decatur with around 93mm 3.7 inches of rain making it a a little damp time to visit. This rainfall is typically spread over 8 days, although this may vary considerably.

On the flip side this corresponds to an average of 10 hours of sunshine per day.

August temperatures in Decatur

Decatur average temperature in August

August rainfall

Decatur average rain in August

August hourly sunshine

Decatur average rain in August

The data used in these monthly averages covers a period of over 100 years right up until last year. As such they are a valid prediction of what to expect for the weather in Decatur in August 2024.