March Weather Outlook for O'Fallon, Missouri

Expect a mix of rain, snow, and thunderstorms throughout the month

Published on Feb. 28, 2026

The March weather forecast for O'Fallon, Missouri calls for a mix of precipitation, including rain showers, wet snow, and thunderstorms at times. Temperatures will range from highs in the 60s to lows in the 30s, with some colder days expected as well. Residents should prepare for changeable and unsettled weather throughout the month.

Why it matters

Understanding the upcoming weather patterns is important for O'Fallon residents to plan their activities, prepare their homes and businesses, and stay safe during potential severe weather events. The March forecast indicates a transition period between winter and spring, with a mix of wintry and spring-like conditions.

The details

The March forecast for O'Fallon includes a variety of weather conditions. There will be periods of partly cloudy skies, but also many days with cloudy skies and chances of precipitation. Rain showers, wet snow, and thunderstorms are all expected at various points throughout the month. Temperatures will range from highs in the 60s Fahrenheit to lows in the 30s, with some colder days in the 40s as well. Winds will generally be light to moderate, coming from the east, northeast, and southwest directions.

  • Partly cloudy skies in the morning will give way to cloudy skies during the afternoon on March 1.
  • Showers of rain and wet snow in the evening on March 3 will become a wintry mix late.
  • Rain with thunderstorms expected by the evening of March 7.
  • Occasional rain with the potential for heavy rainfall on March 9.
  • Showers and thunderstorms likely on March 13.

The players

O'Fallon, Missouri

A city located in St. Charles County, Missouri, about 30 miles west of St. Louis. It has a population of over 90,000 residents.

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What’s next

Residents should monitor the weather forecasts closely and prepare for changing conditions throughout March, including the possibility of severe storms, heavy rainfall, and wintry weather at times.

The takeaway

The March weather in O'Fallon, Missouri will be variable, with a mix of spring-like and wintry conditions. Residents should be prepared to adjust their plans and activities as the weather shifts, and take necessary precautions during any severe weather events.