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

91°F

33°C

Humidity 66%
Wind Speed NE 7 mph
Barometer 30.01 in (1016.1 mb)
Dewpoint 78°F (26°C)
Visibility 10.00 mi
Heat Index106°F (41°C)
Last update 1 Sep 12:53 pm EDT
Extended Forecast for

34 Miles NNW Marathon Airport FL

  • This Afternoon

    This Afternoon: A 40 percent chance of showers and thunderstorms, mainly after 2pm. Mostly sunny, with a high near 90. Heat index values as high as 100. Southwest wind 3 to 5 mph.

    High: 90 °F

    Chance
    T-storms

  • Tonight

    Tonight: A 30 percent chance of showers and thunderstorms, mainly before 2am. Partly cloudy, with a low around 77. Light east wind.

    Low: 77 °F

    Chance
    T-storms

  • Wednesday

    Wednesday: Showers and thunderstorms likely, mainly between 2pm and 3pm. Mostly sunny, with a high near 90. Heat index values as high as 100. Calm wind becoming southwest around 5 mph in the afternoon. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 90 °F

    Mostly Sunny
    then T-storms
    Likely

  • Wednesday Night

    Wednesday Night: Showers and thunderstorms likely, mainly before 7pm. Partly cloudy, with a low around 79. East wind 3 to 5 mph. Chance of precipitation is 60%.

    Low: 79 °F

    T-storms
    Likely then
    Chance
    Showers

  • Thursday

    Thursday: Showers and thunderstorms, mainly between 2pm and 5pm, then showers and possibly a thunderstorm after 5pm. High near 90. Southeast wind 3 to 6 mph. Chance of precipitation is 80%.

    High: 90 °F

    Chance
    T-storms then
    T-storms

  • Thursday Night

    Thursday Night: Showers and possibly a thunderstorm before 8pm, then showers and thunderstorms likely, mainly after 2am. Low around 77. East wind around 8 mph. Chance of precipitation is 80%.

    Low: 77 °F

    T-storms

  • Friday

    Friday: Showers and thunderstorms likely before 8am, then showers and possibly a thunderstorm between 8am and 2pm, then showers and thunderstorms likely after 2pm. High near 90. Southeast wind 6 to 8 mph. Chance of precipitation is 80%.

    High: 90 °F

    T-storms

  • Friday Night

    Friday Night: Showers and thunderstorms likely, mainly before 8pm. Mostly cloudy, with a low around 78. East wind around 7 mph. Chance of precipitation is 60%.

    Low: 78 °F

    T-storms
    Likely

  • Saturday

    Saturday: Showers likely and possibly a thunderstorm, then showers and thunderstorms after 2pm. High near 89. Southeast wind around 5 mph. Chance of precipitation is 90%.

    High: 89 °F

    Showers
    Likely then
    T-storms

Detailed Forecast

This Afternoon
A 40 percent chance of showers and thunderstorms, mainly after 2pm. Mostly sunny, with a high near 90. Heat index values as high as 100. Southwest wind 3 to 5 mph.
Tonight
A 30 percent chance of showers and thunderstorms, mainly before 2am. Partly cloudy, with a low around 77. Light east wind.
Wednesday
Showers and thunderstorms likely, mainly between 2pm and 3pm. Mostly sunny, with a high near 90. Heat index values as high as 100. Calm wind becoming southwest around 5 mph in the afternoon. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Wednesday Night
Showers and thunderstorms likely, mainly before 7pm. Partly cloudy, with a low around 79. East wind 3 to 5 mph. Chance of precipitation is 60%.
Thursday
Showers and thunderstorms, mainly between 2pm and 5pm, then showers and possibly a thunderstorm after 5pm. High near 90. Southeast wind 3 to 6 mph. Chance of precipitation is 80%.
Thursday Night
Showers and possibly a thunderstorm before 8pm, then showers and thunderstorms likely, mainly after 2am. Low around 77. East wind around 8 mph. Chance of precipitation is 80%.
Friday
Showers and thunderstorms likely before 8am, then showers and possibly a thunderstorm between 8am and 2pm, then showers and thunderstorms likely after 2pm. High near 90. Southeast wind 6 to 8 mph. Chance of precipitation is 80%.
Friday Night
Showers and thunderstorms likely, mainly before 8pm. Mostly cloudy, with a low around 78. East wind around 7 mph. Chance of precipitation is 60%.
Saturday
Showers likely and possibly a thunderstorm, then showers and thunderstorms after 2pm. High near 89. Southeast wind around 5 mph. Chance of precipitation is 90%.
Saturday Night
Showers and thunderstorms, mainly before 8pm. Low around 77. Chance of precipitation is 80%.
Sunday
Showers and thunderstorms likely. Mostly sunny, with a high near 89. Chance of precipitation is 60%.
Sunday Night
Showers and thunderstorms likely. Mostly cloudy, with a low around 78. Chance of precipitation is 60%.
Labor Day
Showers and thunderstorms likely. Mostly sunny, with a high near 89. Chance of precipitation is 70%.
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ABOUT THIS FORECAST

 
Point Forecast:
34 Miles NNW Marathon Airport FL
 25.23°N 81.17°W
Last Update:
4:18 am EDT Sep 1, 2026
Forecast Valid:
1pm EDT Sep 1, 2026-6pm EDT Sep 7, 2026
 
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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