Monticello Weather in September

What's the weather like in Monticello (Missouri) in September 2025?

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

September is in the fall / autumn in Monticello and is typically the 4th warmest month of the year. Daytime maximum temperatures average around 26°C (79°F), whilst at night 13°C (55°F) is normal.

Monticello weather averages (imperial / metric)
Daytime temperature 26.1°C 78.9°F
Nightly temperature 13°C 55.3°F
Average temperature 19.5°C 67.1°F
Daily sunshine 8.3 hrs
Avg rainfall 105 mm 4.1 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 3rd wettest month of the year in Monticello with around 105mm 4.1 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 Monticello

Monticello average temperature in September

September rainfall

Monticello average rain in September

September hourly sunshine

Monticello 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 Monticello 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

Monticello weather stats

Monticello weather statistics
Hottest month: July 31.1°C 88°F
Driest month: February 31mm 1.2ins
Sunniest month: July 10.9hrs
Coldest month: January 0.8°C 33.4°F
Wettest month: July 115mm 4.5ins
Map showing location of Monticello (40.11838, -91.71211) Monticello map pin © Google

Locations nearby

Top United States locations