Carthage Weather in September

What's the weather like in Carthage (Illinois) in September 2025?

The climate in Carthage during September can be summarized as warm and damp.

September is in the fall / autumn in Carthage and is typically the 4th warmest month of the year. Daytime maximum temperatures average around 26°C (78°F), whilst at night 12°C (54°F) is normal.

Carthage weather averages (imperial / metric)
Daytime temperature 25.5°C 77.9°F
Nightly temperature 12.3°C 54.1°F
Average temperature 18.9°C 66°F
Daily sunshine 8.3 hrs
Avg rainfall 111 mm 4.4 ins
Rainy days 9 days
Sea temperature 19.6°C 67.4°F
Humidity 72%
Windspeed 14.8kph 9 mph

On average September is the wettest month of the year in Carthage with around 111mm 4.4 inches of rain making it a damp time to visit. This rainfall is typically spread over 9 days, although this may vary considerably.

On the flip side this corresponds to an average of 8.3 hours of sunshine per day.

September temperatures in Carthage

Carthage average temperature in September

September rainfall

Carthage average rain in September

September hourly sunshine

Carthage average rain in September

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 Carthage in September 2025.

Other monthly averages

Best places to visit in September

UV index Best time to go?

Beta

Current (hourly) weather 15 day forecast

Carthage weather stats

Carthage weather statistics
Hottest month: July 30.5°C 86.9°F
Driest month: February 34mm 1.3ins
Sunniest month: July 10.8hrs
Coldest month: January -0.4°C 31.3°F
Wettest month: September 111mm 4.4ins
Map showing location of Carthage (40.41643, -91.13625) Carthage map pin © Google

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