Clear Lake Weather Forecast

    • 42
    • 47

    Mostly Cloudy

    • 35
    • 57

    Partly Sunny

    • 47
    • 55

    Chance Rain

    • 54
    • 60

    Mostly Cloudy

    • 43
    • 65

    Partly Sunny

    • 31
    • 63

    Slight Chance Rain

    • 16
    • 41

    Mostly Sunny

Today 22 Dec Sangamon

Cloudy. Near steady temperature in the mid 40s. South Winds around 10 Mph with Gusts up to 20 Mph.

Tonight 22 Dec Sangamon

Mostly cloudy and not as cool. Near steady temperature in the lower 40s. South Winds 5 to 10 Mph with Gusts up to 20 Mph.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Clear Lake Temperature Statistics

December Temperature

Springfield - Abraham Lincoln Capital Airport (6.2 miles)

  • Lowest 14 December, 2025

    -6 °F

  • Average December

    25.8 °F

  • Highest 18 December, 2025

    54 °F

Climate (2020–Present)

Springfield - Abraham Lincoln Capital Airport (6.2 miles)

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  • Average Low 2020–2025

    44.8 °F

  • Average 2020–2025

    55.1 °F

  • Average High 2020–2025

    65 °F
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