Marathon Weather Forecast

    • 75
    • 81

    Mostly Cloudy

    • 75
    • 81

    Chance Rain Showers

    • 70
    • 80

    Chance Rain Showers

    • 70
    • 76

    Chance Rain Showers

    • 69
    • 76

    Slight Chance Rain Showers

    • 70
    • 76

    Partly Sunny

    • 70
    • 78

    Mostly Cloudy

Today 6 Dec Monroe Middle Keys

Mostly Sunny, becoming partly sunny. A slight chance of Showers. Highs in the lower 80s. East to southeast Winds near 5 Mph. Chance of rain 10 percent.

Tonight 6 Dec Monroe Middle Keys

Partly cloudy with a slight chance of Showers. Lows in the mid 70s. East to southeast Winds near 5 Mph. Chance of rain 20 percent.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Marathon Temperature Statistics

December Temperature

The Florida Keys - Marathon International Airport (2.5 miles)

  • Lowest 3 December, 2025

    73.9 °F

  • Average December

    78.3 °F

  • Highest 1 December, 2025

    82 °F

Climate (2020–Present)

The Florida Keys - Marathon International Airport (2.5 miles)

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  • Average Low 2020–2025

    75.3 °F

  • Average 2020–2025

    80 °F

  • Average High 2020–2025

    85.1 °F
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