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Is it too cold to swim in Key West today?
The latest reading is 82°F (27.6°C), measured November 5, 2026 at 7:18 AM EST at Key West. That is warm water.
Above 77°F, the temperature below which cold water starts to affect breathing control. Temperature is only one factor: check rip current and surf alerts, and swim near lifeguards.
How cold is too cold to swim?Water temperature this week
Hourly water temperature at Key West
Water temperature through the year
Average water temperature by month, satellite 2016–2025. Warmest in August.
Average ocean temperature by month
| Month | Average | Coldest year | Warmest year |
|---|---|---|---|
| January | 74°F | 72°F | 76°F |
| February | 74°F | 72°F | 76°F |
| March | 76°F | 75°F | 78°F |
| April | 79°F | 77°F | 81°F |
| May | 82°F | 80°F | 84°F |
| June | 85°F | 84°F | 86°F |
| July | 87°F | 86°F | 89°F |
| August | 87°F | 86°F | 89°F |
| September | 87°F | 86°F | 87°F |
| October | 83°F | 82°F | 84°F |
| November | 79°F | 77°F | 80°F |
| December | 76°F | 74°F | 77°F |
Other water temperature readings nearby
| Source | Water | Distance | Updated |
|---|---|---|---|
| NASA JPL MUR satellite nearest water | 83°F | 0.1 mi | Nov 3 |
| Satan Shoal, FL (244) buoy | 83°F | 17 mi | 81 min ago |
Water temperatures at nearby beaches
Frequently asked questions
Is it too cold to swim in Key West today?
The latest reading is 82°F (27.6°C), measured November 5, 2026 at 7:18 AM EST at Key West. That is warm water. Above 77°F, the temperature below which cold water starts to affect breathing control. Temperature is only one factor: check rip current and surf alerts, and swim near lifeguards. How cold is too cold?
When is the water warmest at Key West?
Based on satellite data from 2016 to 2025, the water is warmest in August (average 87°F) and coldest in January (average 74°F).
Where does this water temperature come from?
From Key West, a tide station operated by NOAA National Data Buoy Center, 2.6 mi away. See the methodology.
Sources: NOAA National Data Buoy Center; NASA JPL MUR satellite analysis; forecast and alerts from the National Weather Service. Readings are provisional. All Florida water temperatures · Methodology