National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

The Florida Keys - Marathon International Airport (KMTH)

Lat: 24.73°NLon: 81.05°WElev: 13ft.

Fair

84°F

29°C

Humidity 74%
Wind Speed N 14 G 28 mph
Barometer 29.88 in (1011.8 mb)
Dewpoint 75°F (24°C)
Visibility 10.00 mi
Heat Index92°F (33°C)
Last update 19 Aug 7:53 pm EDT
Extended Forecast for

Long Key FL

  • Tonight

    Tonight: Showers likely and possibly a thunderstorm before 9pm, then a chance of showers and thunderstorms after 9pm. Partly cloudy, with a low around 82. Northwest wind 5 to 10 mph. Chance of precipitation is 60%.

    Low: 82 °F

    Showers
    Likely then
    Chance
    Showers

  • Wednesday

    Wednesday: A chance of showers and thunderstorms. Mostly sunny, with a high near 89. Northwest wind 5 to 15 mph. Chance of precipitation is 30%.

    High: 89 °F

    Chance
    T-storms

  • Wednesday Night

    Wednesday Night: A chance of showers and thunderstorms. Partly cloudy, with a low around 83. West wind 10 to 15 mph. Chance of precipitation is 30%.

    Low: 83 °F

    Chance
    T-storms

  • Thursday

    Thursday: A chance of showers and thunderstorms. Mostly sunny, with a high near 89. West wind around 10 mph. Chance of precipitation is 30%.

    High: 89 °F

    Chance
    Showers

  • Thursday Night

    Thursday Night: A chance of showers and thunderstorms. Partly cloudy, with a low around 84. West wind around 5 mph. Chance of precipitation is 30%.

    Low: 84 °F

    Chance
    Showers

  • Friday

    Friday: A chance of showers and thunderstorms. Sunny, with a high near 88. Chance of precipitation is 30%.

    High: 88 °F

    Chance
    Showers

  • Friday Night

    Friday Night: A chance of showers and thunderstorms. Mostly clear, with a low around 83. Chance of precipitation is 30%.

    Low: 83 °F

    Chance
    Showers

  • Saturday

    Saturday: A chance of showers and thunderstorms. Sunny, with a high near 88. Chance of precipitation is 30%.

    High: 88 °F

    Chance
    Showers

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms. Mostly clear, with a low around 83. Chance of precipitation is 30%.

    Low: 83 °F

    Chance
    Showers

Detailed Forecast

Tonight
Showers likely and possibly a thunderstorm before 9pm, then a chance of showers and thunderstorms after 9pm. Partly cloudy, with a low around 82. Northwest wind 5 to 10 mph. Chance of precipitation is 60%.
Wednesday
A chance of showers and thunderstorms. Mostly sunny, with a high near 89. Northwest wind 5 to 15 mph. Chance of precipitation is 30%.
Wednesday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 83. West wind 10 to 15 mph. Chance of precipitation is 30%.
Thursday
A chance of showers and thunderstorms. Mostly sunny, with a high near 89. West wind around 10 mph. Chance of precipitation is 30%.
Thursday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 84. West wind around 5 mph. Chance of precipitation is 30%.
Friday
A chance of showers and thunderstorms. Sunny, with a high near 88. Chance of precipitation is 30%.
Friday Night
A chance of showers and thunderstorms. Mostly clear, with a low around 83. Chance of precipitation is 30%.
Saturday
A chance of showers and thunderstorms. Sunny, with a high near 88. Chance of precipitation is 30%.
Saturday Night
A chance of showers and thunderstorms. Mostly clear, with a low around 83. Chance of precipitation is 30%.
Sunday
A chance of showers and thunderstorms. Sunny, with a high near 88. Chance of precipitation is 30%.
Sunday Night
A chance of showers and thunderstorms. Mostly clear, with a low around 83. Chance of precipitation is 30%.
Monday
A chance of showers and thunderstorms. Sunny, with a high near 88. Chance of precipitation is 30%.
Monday Night
A chance of showers and thunderstorms. Mostly clear, with a low around 83. Chance of precipitation is 30%.
Tuesday
A chance of showers and thunderstorms. Sunny, with a high near 88. Chance of precipitation is 30%.
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ABOUT THIS FORECAST

 
Point Forecast:
Long Key FL
 24.83°N 80.81°W (Elev. 0 ft)
Last Update:
8:15 pm EDT Aug 19, 2025
Forecast Valid:
8pm EDT Aug 19, 2025-6pm EDT Aug 26, 2025
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation