O'Fallon Weather Forecast

    • 55
    • 65

    Increasing Clouds

    • 21
    • 69

    Rain

    • 13
    • 28

    Chance Snow

    • 30
    • 38

    Mostly Cloudy

    • 41
    • 65

    Mostly Sunny

    • 46
    • 70

    Mostly Sunny

Today 14 Mar St. Charles

Partly sunny in the Morning, then clearing. Highs in the lower 60s. Southeast Winds 10 to 15 Mph.

Tonight 14 Mar St. Charles

Partly cloudy. Not as cool with Lows in the mid 50s. South Winds 10 to 15 Mph. Gusts up to 30 Mph after midnight.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

O'Fallon Temperature Statistics

March Temperature

St. Louis, Spirit Of St. Louis Airport (10.6 miles)

  • Lowest 1 March, 2026

    27 °F

  • Average March

    54 °F

  • Highest 10 March, 2026

    84.9 °F

Climate (2021–Present)

St. Louis, Spirit Of St. Louis Airport (10.6 miles)

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  • Average Low 2021–2026

    46 °F

  • Average 2021–2026

    57.2 °F

  • Average High 2021–2026

    68.6 °F
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