Georgia Coast
St. Simons Island Water Temperature
The village pier, St. Simons Sound, and Gould's Inlet at the east end.
That is about 7°F warmer than average for this time of year, and cooling over the last two weeks. The October average here is 75°F.
Updated Friday, October 2 — sea-surface temperature modeled for St. Simons Island by Open-Meteo.
For swimming
Very warm
Bath-warm. Pleasant, though it stops being much relief from the heat of the day.
For fishing
Hot — fish the edges of the day
Early and late is the play. Through the middle of the day fish drop into deeper channels and passes where there's moving water and more oxygen.
The last two weeks
Daily average sea-surface temperature, °F.
St. Simons Island water temperature by month
Averaged from 3 years of daily sea-surface temperature (2023–2025). The range column is the coolest and warmest daily average recorded in that month over the period — a guide to how much any given year can differ, not a record high and low.
| Month | Average | Range | Swimming |
|---|---|---|---|
| January | 54°F | 48–58°F | Cold |
| February | 58°F | 54–67°F | Cold |
| March | 64°F | 57–71°F | Bracing |
| April | 71°F | 66–77°F | Cool but comfortable |
| May | 78°F | 72–84°F | Warm |
| June | 83°F | 75–88°F | Very warm |
| July | 87°F | 85–90°F | Very warm |
| August | 87°F | 81–90°F | Very warm |
| September | 82°F | 79–86°F | Very warm |
| Octobernow | 75°F | 69–82°F | Warm |
| November | 68°F | 61–75°F | Cool but comfortable |
| December | 59°F | 56–64°F | Cold |
Warmest on average in July at 87°F; coolest in January at 54°F.
The water at St. Simons Island
St. Simons has land-based fishing that actually works — the pier in the village reaches into the sound where sheepshead, drum, and reds move with the tide, and Gould's Inlet at the east end is a shifting sandbar fishery you can wade at the right water level. Out in the sound and along the beaches, tripletail are the Golden Isles specialty, drifting on the surface near anything floating from spring into summer. The marsh behind the island holds the same redfish and trout as the rest of the Georgia coast, on the same enormous tides. Most visitors come for the beach and the flat, shaded bike paths under the live oaks, which is its own good reason to check a forecast. Summer thunderstorms build inland and roll east over the island most afternoons.
the pier, the sound & the beach
What moves the water temperature here
The Gulf shelf off this coast is shallow, which is why the water swings so much more between summer and winter than open ocean at the same latitude does. Shallow water heats fast and gives that heat up fast: a single strong winter cold front can pull the inshore bays several degrees down in a couple of days, while the beaches a mile offshore barely move. Wind direction matters too — a sustained offshore breeze can pull cooler water up from below and drop the beach temperature noticeably in a morning.
Inshore bays, canals and flats run warmer than the beach through the summer and colder through the winter, for the same reason. The reading above is for the open water at St. Simons Island; expect the back bays to be a few degrees either side of it depending on the season.
Common questions
- What is the water temperature at St. Simons Island right now?
- The water at St. Simons Island is currently about 82°F (28°C). The October average here is 75°F.
- Is the water warm enough to swim at St. Simons Island in October?
- October averages 75°F at St. Simons Island, which most people would call warm. About as good as it gets — warm enough to stay in for hours without getting chilled.
- When is the water warmest at St. Simons Island?
- July is the warmest month on average at 87°F, and January the coolest at 54°F. 6 months of the year average 75°F or above.
- Why does the water temperature change so quickly here?
- The Gulf shelf off this coast is shallow, so it heats and cools far faster than deep open ocean. A strong winter cold front can pull the inshore water down several degrees in a couple of days, and a sustained offshore wind can drop beach temperatures in a single morning by pulling cooler water up from below.