Texas Gulf Coast
Rockport Water Temperature
Aransas and Copano bays, Redfish Bay grass, and a century of guiding tradition.
That is about 5°F warmer than average for this time of year, and holding steady over the last two weeks. The October average here is 81°F.
Updated Saturday, October 3 — sea-surface temperature modeled for Rockport by Open-Meteo.
Out in the open Gulf, NOAA buoy 42002 — 247 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.
Rockport 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 | 59°F | 52–66°F | Cold |
| February | 61°F | 56–67°F | Bracing |
| March | 68°F | 60–73°F | Cool but comfortable |
| April | 74°F | 71–79°F | Cool but comfortable |
| May | 81°F | 75–86°F | Warm |
| June | 86°F | 83–88°F | Very warm |
| July | 86°F | 85–88°F | Very warm |
| August | 88°F | 86–90°F | Bath water |
| September | 86°F | 82–88°F | Very warm |
| Octobernow | 81°F | 74–86°F | Warm |
| November | 74°F | 64–80°F | Cool but comfortable |
| December | 66°F | 60–71°F | Bracing |
Warmest on average in August at 88°F; coolest in January at 59°F.
The water at Rockport
Rockport and Fulton have built a hundred years of guiding on the shallow bays behind San Jose Island — Aransas, Copano, St. Charles, and the seagrass of Redfish Bay, where prop-scar rules keep the grass beds intact. Redfish are the headliner, tailing on the flats and crawling the shorelines, with big trout over grass and black drum stacked in the deeper guts through winter. The Lighthouse Lakes paddling trails wind through black mangrove nearby, putting kayak anglers into water no skiff can reach. Copano takes fresh water from the Aransas and Mission rivers, so it stains after rain while the outer bays stay clearer. Whooping cranes winter in the refuge marsh just up the bay, which tells you how healthy this estuary still is.
Aransas & Copano Bays
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 Rockport; 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 Rockport right now?
- The water at Rockport is currently about 86°F (30°C). The October average here is 81°F.
- Is the water warm enough to swim at Rockport in October?
- October averages 81°F at Rockport, 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 Rockport?
- August is the warmest month on average at 88°F, and January the coolest at 59°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.