Byrnes Mill Weather Forecast

    • 66
    • 85

    Chance Rain Showers

    • 64
    • 85

    Rain Showers Likely

    • 70
    • 91

    Mostly Sunny

    • 70
    • 91

    Chance Thunderstorms

    • 59
    • 87

    Rain Showers Likely

    • 55
    • 76

    Chance Thunderstorms

Today 15 May Jefferson

Partly sunny. A slight chance of Showers and Thunderstorms this morning. Highs in the mid 80s. South Winds 10 to 15 Mph with Gusts up to 25 Mph. Chance of rain 20 percent.

Tonight 15 May Jefferson

Mostly cloudy. A slight chance of Showers and Thunderstorms after midnight. Lows in the mid 60s. South Winds 5 to 10 Mph with Gusts up to 20 Mph. Chance of rain 20 percent.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Byrnes Mill Temperature Statistics

May Temperature

St. Louis, Spirit Of St. Louis Airport (15.5 miles)

  • Lowest 7 May, 2026

    36.6 °F

  • Average May

    59 °F

  • Highest 12 May, 2026

    82.7 °F

Climate (2021–Present)

St. Louis, Spirit Of St. Louis Airport (15.5 miles)

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  • Average Low 2021–2026

    46 °F

  • Average 2021–2026

    57.4 °F

  • Average High 2021–2026

    68.8 °F
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