Flat Lake Weather Forecast

    • -21
    • -10

    Cold

    • -24
    • -3

    Cold

    • -16
    • -7

    Cold

    • -6
    • 15

    Partly Sunny

    • -5
    • 8

    Cold

    • -8
    • 9

    Cold

    • -7
    • 8

    Cold

Today 23 Jan McHenry

Mostly cloudy. Northwest Winds around 5 Mph. Wind Chills around 25 below.

Tonight 23 Jan McHenry

Mostly cloudy in the evening then clearing. Lows around 25 below. West Winds around 5 Mph, becoming south after midnight. Wind Chills around 35 below.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Flat Lake Temperature Statistics

January Temperature

Harvey Municipal Airport (22.4 miles)

  • Lowest 17 January, 2026

    -9.4 °F

  • Average January

    17.2 °F

  • Highest 7 January, 2026

    41 °F

Climate (2021–Present)

Harvey Municipal Airport (22.4 miles)

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  • Average Low 2021–2026

    30.2 °F

  • Average 2021–2026

    41.1 °F

  • Average High 2021–2026

    51.9 °F
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