Chatham Weather Forecast

    • 65
    • 79

    Mostly Sunny

    • 64
    • 79

    Mostly Sunny

    • 66
    • 81

    Mostly Sunny

    • 66
    • 82

    Slight Chance Rain Showers

    • 63
    • 75

    Chance Rain Showers

    • 62
    • 72

    Chance Rain Showers

Today 15 Sep Central Cook

Sunny. Highs in the lower 80s Inland, but only in the upper 70s near the lake. East Winds 5 to 10 Mph.

Tonight 15 Sep Central Cook

Mostly clear. Lows in the mid 60s. East Winds around 5 Mph.

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Chatham Temperature Statistics

September Temperature

Chicago, Chicago Midway Airport (7.5 miles)

  • Lowest 7 September, 2025

    48.9 °F

  • Average September

    66.6 °F

  • Highest 12 September, 2025

    84.9 °F

Climate (2020–Present)

Chicago, Chicago Midway Airport (7.5 miles)

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  • Average Low 2020–2025

    46.6 °F

  • Average 2020–2025

    54.2 °F

  • Average High 2020–2025

    61.8 °F
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