O'Fallon weather in September (Illinois, United States of America)
How is September weather typically in O'Fallon? Find out what kind of weather to expect during this month.
Temperatures
September in O'Fallon generally includes high temperatures and high rainfall. Anticipate daytime temperatures around 27°C, while night temperatures can drop to 15°C.
Precipitation
O'Fallon in September usually receives high rainfall, averaging around 102 mm for the month. Rain is expected on roughly 10 days.Average sunshine
With approximately 235 hours hours of sun, the days are filled with brightness. It makes it a perfect month for outdoor activities.If your ideal day consists of dry skies and moderate temperatures October generally stands out with the best circumstances. While January, February and December tend to showcase less optimal conditions.
For an in-depth look at the yearly conditions, visit our specialized O'Fallon climate page with graphs.
O'Fallon, monthly averages in September
Min Temperature
15°C
Max Temperature
27°C
Chance of Rain
33%
Precipitation
102 mm
Rainy days
10 days
Humidity
71% *
Sunshine
235 hours *
Percentage Sunshine
63% *
Where to go in the United States of America in September
Find out more about the weather in the United States of America and which places have the best travel conditions in this month.
perfect weather
pleasant
tolerable
unpleasant
poor
So, what should you wear in this month?
It's going to be warm! Consider airy clothing, t-shirts, and other summer clothes. Shorts for men made of cotton or linen are good options for staying cool. However, there's a good chance of rain, so bring a raincoat just in case.What To Do
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Interested in more climate information?
This site provides you with all the information you need about the climate in O'Fallon.
Our site offers climate and forecast data for every country in the world. Are you going to the United States of America? On this website you can find historical weather averages for many cities in the United States of America. Not sure yet where to go? We now have a tool which recommends destinations that suit your ideal travel conditions. Find out where to go with our weather planner.
