St. Clair Weather Forecast

    • 22
    • 34

    Mostly Cloudy

    • 27
    • 37

    Mostly Cloudy

    • 20
    • 37

    Rain/Snow Likely

    • 13
    • 28

    Mostly Cloudy

    • 29
    • 35

    Chance Rain/Snow

    • 27
    • 42

    Rain/Snow

Today 5 Dec Allegheny

Partly sunny in the Morning, then becoming cloudy. Highs in the mid 30s. Southeast Winds around 5 Mph, becoming southwest around 5 Mph in the afternoon.

Tonight 5 Dec Allegheny

Mostly cloudy. Lows in the lower 20s. Southwest Winds around 5 Mph.

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St. Clair Temperature Statistics

December Temperature

Pittsburgh - Allegheny County Airport (4.3 miles)

  • Lowest 3 December, 2025

    27 °F

  • Average December

    29.2 °F

  • Highest 1 December, 2025

    32 °F

Climate (2020–Present)

Pittsburgh - Allegheny County Airport (4.3 miles)

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  • Average Low 2020–2025

    46.1 °F

  • Average 2020–2025

    54.6 °F

  • Average High 2020–2025

    63.3 °F
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