Beaches with warm water in Marathon

7 beaches scored for warm water in Marathon, from measured data with the source and date on every fact. Top score 8.4 of 10 at Campground Beach. That is 7 of the 7 ranked beaches in Marathon.

  • Scored7 beaches
  • 75 F or warmerFebruary to December
  • WhereMarathon
  • Top score8.4 of 10 at Campground Beach

7 beaches in Marathon with warm water. Ranked by warm water score, then Beach Score, updated Sep 10, 2026. Rankings reflect typical conditions, not today.

Sea temperature by month

Warmest in August at 88 F. 11 months at 75 F or more, February to December. Averaged over the 7 listed beaches.

  1. Campground Beach: sandy beach with calm shallow water and mangrove shoreline#1
    Marathon, Florida
    Warm water8.4 of 10Mean sea temperature 82 F, 11 months at 75 F or more, February to December.
    Parking · Pier · BathroomsView beach
  2. Aerial view of Public Beach in Marathon, Florida, shoreline and surroundings, USDA NAIP imagery from May 2023#2
    Marathon, Florida
    Warm water8.4 of 10Mean sea temperature 82 F, 11 months at 75 F or more, February to December.
    Parking · Sunrise over water · PierView beach
  3. Calusa Beach: shallow water, sandy beach, blue sky with white clouds#3
    Marathon, Florida
    Warm water8.3 of 10Mean sea temperature 82 F, 11 months at 75 F or more, February to December.
    Parking · Free parking · Sunset over waterView beach
  4. Loggerhead Beach: shallow water, sandy beach, blue sky with white clouds#4
    Marathon, Florida
    Warm water8.3 of 10Mean sea temperature 82 F, 11 months at 75 F or more, February to December.
    Parking · Free parking · Restaurants and barsView beach
  5. Aerial view of Coca Plum Beach in Marathon, Florida, shoreline and surroundings, USDA NAIP imagery from May 2023#5
    Marathon, Florida
    Warm water8.3 of 10Mean sea temperature 82 F, 11 months at 75 F or more, February to December.
    Parking · Pier · Hotels nearbyView beach
  6. Sombrero Beach: sandy beach with umbrella, palm trees, calm water, clear sky#6
    Marathon, Florida
    Warm water8.3 of 10Mean sea temperature 82 F, 11 months at 75 F or more, February to December.
    Parking · Pier · BathroomsView beach
  7. Sandspur Beach: driftwood on sandy beach with turquoise ocean and sky#7
    Marathon, Florida
    Warm water8.3 of 10Mean sea temperature 82 F, 11 months at 75 F or more, February to December.
    Parking · Free parking · BathroomsView beach
7 beaches
7

Compare beaches with warm water

BeachWarm water scoreMean sea temperatureParkingBeach Score
Campground BeachMarathon8.482 FYes4.6
Public BeachMarathon8.482 FYes4.6
Calusa BeachMarathon8.382 FYes6.4
Loggerhead BeachMarathon8.382 FYes5.4
Coca Plum BeachMarathon8.382 FYes4.7
Sombrero BeachMarathon8.382 FYes4.7
Sandspur BeachMarathon8.382 FYes4.6

How warm water works

Sea temperature lags the air by a month or two, so the warmest water comes in late summer and the coolest in late winter. A beach counts as warm water when at least six months average 24 C (75 F) or more, which is warm enough to swim without a wetsuit.

How we verify warm water

Scored from monthly sea surface temperature over the last three years of marine model data. Counts as warm when at least six months average 75 F (24 C) or more. Sources and methodology

Where in Marathon

All of the listed beaches are in Marathon.

Today in Marathon

Fair beach day, 60 of 100

Wind up to 22 mph, waves up to 2.2 ft, 26% rain chance, high 87 F.

Wind, up to22 mph
Waves, up to2.2 ft
Rain chance26%
High87 F

Forecast at each area's centre from Open-Meteo, refreshed hourly; the rating rule is on the methodology page. The ranking below reflects typical conditions, not today.

When to go

Warmest sea: August at 88 F (31 C). Calmest water: September, mean daily maximum wave 2.0 ft. Fewest rain days: January, February, November.

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