Grassy Key Weather Forecast

    • 82
    • 92

    Partly Sunny

    • 82
    • 92

    Chance Rain Showers

    • 82
    • 91

    Chance Thunderstorms

    • 81
    • 91

    Chance Thunderstorms

    • 81
    • 91

    Chance Thunderstorms

    • 81
    • 91

    Chance Thunderstorms

Today 26 Aug Monroe Middle Keys

Mostly sunny with a slight chance of Showers and Thunderstorms. Highs in the lower 90s. Northeast to east Winds near 5 Mph. Chance of rain 10 percent.

Tonight 26 Aug Monroe Middle Keys

Partly cloudy with a slight chance of Showers and Thunderstorms. Lows in the lower to mid 80s. Northeast to east Winds near 5 Mph. Chance of rain 20 percent.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Grassy Key Temperature Statistics

August Temperature

The Florida Keys - Marathon International Airport (6.2 miles)

  • Lowest 7 August, 2025

    75.7 °F

  • Average August

    86.5 °F

  • Highest 18 August, 2025

    93.7 °F

Climate (2020–Present)

The Florida Keys - Marathon International Airport (6.2 miles)

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  • Average Low 2020–2025

    75.4 °F

  • Average 2020–2025

    80 °F

  • Average High 2020–2025

    85.2 °F
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