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O'Fallon
Weather averages
ClimateForecastNovemberDecember >>

O'Fallon (IL) Climate by Month

The graphs below provide an overview of the climate in O'Fallon (Illinois), the United States of America. They present long-term patterns and averages of weather conditions over a 30-year period.

Average day and night temperature

The mean minimum and maximum temperatures over the year.

Monthly hours of sunshine

The average monthly total hours of sunshine over the year
* Data from: St. Louis, the United States of America (25 KM, 15 Miles).

Daily percent of sunshine

The mean percent of hours of sunhours during the day over the year
* Data from: St. Louis, the United States of America (25 KM, 15 Miles).

Monthly precipitation

The mean monthly precipitation over the year, including rain, snow, hail etc.

Monthly rainy days

The average number of days each month with rain, snow, hail etc.

Average humidity

The mean monthly relative humidity over the year
* Data from: St. Louis, the United States of America (25 KM, 15 Miles).

Forecast for O'Fallon (IL)

Sat   Nov 02
19°C | 3°C
SE 14 km/h
almost clear and no rain

almost clear and no rain

hourly forecast
Sun   Nov 03
22°C | 9°C
SE 18 km/h
10 mm
broken clouds and thunder

broken clouds and thunder

hourly forecast
Mon   Nov 04
24°C | 17°C
S 25 km/h
23 mm
broken clouds and thunder

broken clouds and thunder

hourly forecast
5-Day Forecast 10-Day Forecast

The best time of year to visit O'Fallon in the United States of America

During the months of April, May and October you are most likely to experience good weather with pleasant average temperatures that fall between 20°C and 26°C.

Other facts from our historical weather data:

  • Which is the warmest month in O'Fallon?
    July has an average maximum temperature of 31°C and is the warmest month of the year.
  • Which is the coldest month in O'Fallon?
    The coldest month is January with an average maximum temperature of 5°C.
  • Which is the wettest month in O'Fallon?
    June tops the wettest month list with 142 mm of rainfall.
  • Which is the driest month in O'Fallon?
    January is the driest month with 56 mm of precipitation.
  • Which is the sunniest month in O'Fallon?
    July is the sunniest month with an average of 311 hours of sunshine.

    • No idea where to travel to this year? We have a tool that recommends destinations based on your ideal conditions. Find out where to go with our weather planner.

     

     


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