First Coast
St. Augustine Water Temperature
Matanzas & Tolomato rivers and the Atlantic surf.
Sea-surface temperature
WarmHolding steady · last two weeks
That is about 3°F warmer than average for this time of year, and holding steady over the last two weeks. The November average here is 72°F.
Updated Saturday, November 7 — sea-surface temperature modeled for St. Augustine by Open-Meteo.
Out in the open Gulf, NOAA buoy 41117 — 16 miles offshore — is reading 76°F. Deep water offshore runs cooler than the shallows in summer and warmer in winter, so it won't match the beach.
For swimming
Warm
About as good as it gets — warm enough to stay in for hours without getting chilled.
For fishing
Peak season
Snook, redfish and tarpon are all active and feeding. The tarpon migration through the passes runs at the upper end of this range.
The last two weeks
| Date | Average |
|---|---|
| Oct 25 | 73.6°F |
| Oct 26 | 72.9°F |
| Oct 27 | 72.3°F |
| Oct 28 | 72.9°F |
| Oct 29 | 72.9°F |
| Oct 30 | 72.7°F |
| Oct 31 | 72.9°F |
| Nov 1 | 72.9°F |
| Nov 2 | 72.7°F |
| Nov 3 | 72.9°F |
| Nov 4 | 74.1°F |
| Nov 5 | 75°F |
| Nov 6 | 75.4°F |
| Nov 7 | 75°F |
St. Augustine 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 | Range | Average |
|---|---|---|
JanJanuary Bracing | 54–66°F | 61°F |
FebFebruary Bracing | 58–69°F | 63°F |
MarMarch Bracing | 60–71°F | 66°F |
AprApril Cool but comfortable | 67–76°F | 72°F |
MayMay Warm | 74–81°F | 78°F |
JunJune Warm | 77–85°F | 81°F |
JulJuly Very warm | 80–88°F | 84°F |
AugAugust Very warm | 80–87°F | 85°F |
SepSeptember Very warm | 81–86°F | 83°F |
OctOctober Warm | 74–83°F | 78°F |
NovNovembernow Cool but comfortable | 67–77°F | 72°F |
DecDecember Bracing | 61–69°F | 65°F |
Warmest
85°FAugust
Coolest
61°FJanuary
Warmest on average in August at 85°F; coolest in January at 61°F.
The water at St. Augustine
St. Augustine sits on the Atlantic side, where the Matanzas and Tolomato rivers and the St. Augustine Inlet drive a strong redfish, trout, and flounder fishery. Whiting and pompano work the surf, and a run offshore reaches kingfish, snapper, and cobia. The bigger Atlantic tides here mean current is a constant factor around the inlet.
Matanzas Bay & the Atlantic
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. Augustine; 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. Augustine right now?
- The water at St. Augustine is currently about 75°F (24°C). The November average here is 72°F.
- Is the water warm enough to swim at St. Augustine in November?
- November averages 72°F at St. Augustine, which most people would call cool but comfortable. Refreshing rather than cold — comfortable once you're past the first minute.
- When is the water warmest at St. Augustine?
- August is the warmest month on average at 85°F, and January the coolest at 61°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.