Marathon Weather Forecast

    • 69
    • 75

    Chance Rain Showers

    • 68
    • 78

    Slight Chance Rain Showers

    • 70
    • 79

    Mostly Sunny

    • 72
    • 80

    Mostly Sunny

    • 71
    • 81

    Mostly Sunny

    • 66
    • 79

    Partly Sunny

    • 63
    • 75

    Partly Sunny

Today 21 Jan Monroe Middle Keys

Partly sunny with a slight chance of Showers. Windy, becoming breezy. Highs in the mid 70s. Northeast Winds near 20 Mph, decreasing to 15 to 20 Mph. Chance of rain 10 percent.

Tonight 21 Jan Monroe Middle Keys

Partly to mostly cloudy with a chance of Showers. Breezy early. Lows in the upper 60s. Northeast Winds 15 to 20 Mph, decreasing to near 15 Mph. Chance of rain 30 percent.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Marathon Temperature Statistics

January Temperature

The Florida Keys - Marathon International Airport (2.5 miles)

  • Lowest 16 January, 2026

    51.1 °F

  • Average January

    70.3 °F

  • Highest 9 January, 2026

    81 °F

Climate (2021–Present)

The Florida Keys - Marathon International Airport (2.5 miles)

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  • Average Low 2021–2026

    75.4 °F

  • Average 2021–2026

    80.1 °F

  • Average High 2021–2026

    85.1 °F
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