Treasure Coast
Fort Pierce Water Temperature
The Fort Pierce Inlet jetties and the north end of the lagoon.
That is right about average for this time of year, and holding steady over the last two weeks. The September average here is 86°F.
Updated Monday, September 21 — sea-surface temperature modeled for Fort Pierce by Open-Meteo.
Out in the open Gulf, NOAA buoy 41010 — 146 miles offshore — is reading 86°F. Deep water offshore runs cooler than the shallows in summer and warmer in winter, so it won't match the beach.
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.
Fort Pierce 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 | 70°F | 62–76°F | Cool but comfortable |
| February | 72°F | 65–76°F | Cool but comfortable |
| March | 74°F | 71–78°F | Cool but comfortable |
| April | 77°F | 74–80°F | Warm |
| May | 81°F | 77–86°F | Warm |
| June | 84°F | 79–87°F | Very warm |
| July | 86°F | 83–89°F | Very warm |
| August | 87°F | 84–89°F | Very warm |
| Septembernow | 86°F | 83–88°F | Very warm |
| October | 80°F | 77–87°F | Warm |
| November | 76°F | 72–80°F | Warm |
| December | 72°F | 66–76°F | Cool but comfortable |
Warmest on average in August at 87°F; coolest in January at 70°F.
The water at Fort Pierce
Fort Pierce Inlet is a deep, hard-running cut with jetties on both sides and a state park on the north — one of the most reliable land-based snook, tarpon, and redfish spots on the Treasure Coast. The inlet's current sweeps bait through in a hurry, and the lagoon behind it holds trout and reds over grass. It's also the closest inlet to some very good nearshore reef.
Fort Pierce Inlet & the jetties
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 Fort Pierce; 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 Fort Pierce right now?
- The water at Fort Pierce is currently about 86°F (30°C). The September average here is 86°F.
- Is the water warm enough to swim at Fort Pierce in September?
- September averages 86°F at Fort Pierce, which most people would call very warm. Bath-warm. Pleasant, though it stops being much relief from the heat of the day.
- When is the water warmest at Fort Pierce?
- August is the warmest month on average at 87°F, and January the coolest at 70°F. 8 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.