Lake Forest Weather Forecast

    • 56
    • 83

    Mostly Sunny

    • 54
    • 82

    Mostly Sunny

    • 56
    • 83

    Mostly Sunny

    • 56
    • 82

    Partly Sunny

    • 60
    • 82

    Slight Chance Rain Showers

    • 60
    • 82

    Chance Rain Showers

Today 16 Sep Summit

Partly cloudy. Highs in the mid 80s. Southeast Winds around 5 Mph.

Tonight 16 Sep Summit

Mostly clear. Lows in the mid 50s. Northeast Winds 5 to 10 Mph, becoming east after midnight.

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Lake Forest Temperature Statistics

September Temperature

Portage County Airport (11.2 miles)

  • Lowest 8 September, 2025

    37.8 °F

  • Average September

    60 °F

  • Highest 3 September, 2025

    80.1 °F

Climate (2020–Present)

Portage County Airport (11.2 miles)

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  • Average Low 2020–2025

    40.7 °F

  • Average 2020–2025

    50.1 °F

  • Average High 2020–2025

    60 °F
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