Ontario Weather Forecast

    • 58
    • 79

    Decreasing Clouds

    • 59
    • 78

    Partly Sunny

    • 57
    • 80

    Slight Chance Thunderstorms

    • 51
    • 72

    Mostly Sunny

    • 47
    • 66

    Mostly Sunny

    • 45
    • 67

    Mostly Sunny

Today 20 Aug Vernon

Patchy fog early this morning. Partly sunny. Highs in the upper 70s. Northeast Winds around 5 Mph.

Tonight 20 Aug Vernon

Partly cloudy. Lows around 60. East Winds around 5 Mph.

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Ontario Temperature Statistics

August Temperature

Sparta, Sparta / Fort McCoy Airport (17.4 miles)

  • Lowest 1 August, 2025

    44.6 °F

  • Average August

    70.8 °F

  • Highest 15 August, 2025

    91.2 °F

Climate (2020–Present)

Sparta, Sparta / Fort McCoy Airport (17.4 miles)

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  • Average Low 2020–2025

    34.5 °F

  • Average 2020–2025

    47.3 °F

  • Average High 2020–2025

    57.9 °F
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