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.

Mostly Cloudy

86°F

30°C

Humidity 72%
Wind Speed NE 3 mph
Barometer 29.90 in (1012.4 mb)
Dewpoint 76°F (24°C)
Visibility 10.00 mi
Heat Index96°F (36°C)
Last update 17 Oct 4:53 pm EDT
Extended Forecast for

23 Miles NNW Long Key FL

  • This Afternoon

    This Afternoon: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 86. West wind around 6 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 86 °F

    Chance
    T-storms

  • Tonight

    Tonight: Showers and thunderstorms likely, mainly before 1am. Mostly cloudy, with a low around 72. North wind 9 to 13 mph, with gusts as high as 24 mph. Chance of precipitation is 70%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    Low: 72 °F

    Showers
    Likely

  • Sunday

    Sunday: A 50 percent chance of showers and thunderstorms, mainly after 11am. Partly sunny, with a high near 83. Breezy, with a northeast wind 15 to 17 mph, with gusts as high as 28 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 83 °F

    Chance
    T-storms and
    Breezy

  • Sunday Night

    Sunday Night: A 40 percent chance of showers and thunderstorms. Some of the storms could produce heavy rainfall. Mostly cloudy, with a low around 72. Breezy, with a northeast wind 13 to 18 mph, with gusts as high as 30 mph.

    Low: 72 °F

    Heavy Rain
    and Breezy
    then Chance
    Showers

  • Monday

    Monday: A 30 percent chance of showers and thunderstorms, mainly after 2pm. Mostly sunny, with a high near 85. Breezy, with a northeast wind 15 to 18 mph, with gusts as high as 28 mph.

    High: 85 °F

    Breezy.
    Slight Chance
    T-storms then
    Chance
    Showers

  • Monday Night

    Monday Night: A 30 percent chance of showers before 8pm. Mostly clear, with a low around 71. Breezy, with a northeast wind 13 to 16 mph, with gusts as high as 25 mph.

    Low: 71 °F

    Chance
    Showers and
    Breezy then
    Partly Cloudy

  • Tuesday

    Tuesday: Sunny, with a high near 85. Breezy, with a northeast wind around 16 mph, with gusts as high as 24 mph.

    High: 85 °F

    Sunny and
    Breezy

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 72. Windy, with a north wind 16 to 21 mph, with gusts as high as 24 mph.

    Low: 72 °F

    Mostly Clear
    and Windy

  • Wednesday

    Wednesday: Sunny, with a high near 83. Breezy, with a northeast wind 11 to 17 mph, with gusts as high as 22 mph.

    High: 83 °F

    Sunny and
    Breezy then
    Sunny

Detailed Forecast

This Afternoon
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 86. West wind around 6 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Tonight
Showers and thunderstorms likely, mainly before 1am. Mostly cloudy, with a low around 72. North wind 9 to 13 mph, with gusts as high as 24 mph. Chance of precipitation is 70%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Sunday
A 50 percent chance of showers and thunderstorms, mainly after 11am. Partly sunny, with a high near 83. Breezy, with a northeast wind 15 to 17 mph, with gusts as high as 28 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Sunday Night
A 40 percent chance of showers and thunderstorms. Some of the storms could produce heavy rainfall. Mostly cloudy, with a low around 72. Breezy, with a northeast wind 13 to 18 mph, with gusts as high as 30 mph.
Monday
A 30 percent chance of showers and thunderstorms, mainly after 2pm. Mostly sunny, with a high near 85. Breezy, with a northeast wind 15 to 18 mph, with gusts as high as 28 mph.
Monday Night
A 30 percent chance of showers before 8pm. Mostly clear, with a low around 71. Breezy, with a northeast wind 13 to 16 mph, with gusts as high as 25 mph.
Tuesday
Sunny, with a high near 85. Breezy, with a northeast wind around 16 mph, with gusts as high as 24 mph.
Tuesday Night
Mostly clear, with a low around 72. Windy, with a north wind 16 to 21 mph, with gusts as high as 24 mph.
Wednesday
Sunny, with a high near 83. Breezy, with a northeast wind 11 to 17 mph, with gusts as high as 22 mph.
Wednesday Night
Mostly clear, with a low around 71. Breezy.
Thursday
A 20 percent chance of showers. Sunny, with a high near 82. Breezy.
Thursday Night
A 10 percent chance of showers. Partly cloudy, with a low around 70.
Friday
A 20 percent chance of showers. Sunny, with a high near 81.
Friday Night
A 10 percent chance of showers. Mostly clear, with a low around 70.
Saturday
A chance of showers and thunderstorms. Sunny, with a high near 82.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
23 Miles NNW Long Key FL
 25.14°N 80.95°W
Last Update:
4:17 pm EDT Oct 17, 2026
Forecast Valid:
5pm EDT Oct 17, 2026-6pm EDT Oct 24, 2026
 
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Additional Resources

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Chance of Precipitation