Amelia Island water temperature in December
Key facts
The Atlantic off Amelia Island averages 62°F in December — brisk. A short swim is fine if you keep moving; a spring suit helps. That is 10.6°F below the island’s annual average of 72.6°F, and 8.4°F down from November.
- Average daily high to low
- Ocean temperature
December in the water
December water is cold and getting colder, and the wind off it makes the beach feel colder than the thermometer says. This is a walking, shelling and whale-watching beach for the next three months, not a swimming one.
At 62°F the sea is 10.6°F below the island’s annual average of 72.6°F. The air reaches 66.3°F in December, a gap of 4.3°F, small enough that the ocean gives you no relief from the heat.
What to wear
A 3/2 full suit is the normal choice. A spring suit works for a short surf on a calm, sunny day.
Where this number comes from
62°F is the mean of every hourly reading for December across 2023, 2024 and 2025 at NOAA CO-OPS station 8720218, Mayport (Bar Pilots Dock), FL — about 30 km south of the island. The Fernandina Beach station on the island has no water-temperature sensor, so no on-island long record exists to average. We would rather say that plainly than publish an on-island figure we cannot support.
A monthly mean is not a forecast. The real ocean in any given December week moves several degrees around this figure, and a hard south-westerly can pull colder water up onto the shelf in a day. For the reading right now, the offshore waverider buoy 41112 (Offshore Fernandina Beach, FL, 17 km ENE) reports water temperature alongside wave height — that is what feeds our surf report and beach conditions.
December against the months either side
| November | December | January | |
|---|---|---|---|
| Sea temperature | 70.4°F | 62°F | 57.9°F |
| Our reading | Comfortable | Brisk | Cold |
| Air high | 72.4°F | 66.3°F | 64.3°F |
The annual mean is 72.6°F, and the sea lags the air by about two months in both directions — see water temperature by month for why that lag matters more than the raw number.
Next and previous months
Planning a December beach day
Part of Amelia Island water temperature by month.
Frequently asked questions
- What is the water temperature at Amelia Island in December?
- The ocean averages 62°F (16.7°C) in December, from three years of hourly NOAA readings at the nearest sensor with a long record — station 8720218, 30 km south of the island. A given week moves several degrees around that.
- Can you swim at Amelia Island in December?
- Brisk at 62°F. A short swim is fine if you keep moving; a spring suit helps.
- Do you need a wetsuit at Amelia Island in December?
- A 3/2 full suit is the normal choice. A spring suit works for a short surf on a calm, sunny day.