Portstewart Strand sea temperature
Sea-surface temperature for Portstewart Strand, United Kingdom, with the 7-day outlook and what to wear.
What is the sea temperature at Portstewart Strand today? (3 Sept)
The sea at Portstewart Strand is 16.6 °C today. A 4/3 keeps a two-hour session comfortable; many people add boots. Most people add boots on longer sessions. The sea and the air are within a degree or so of each other.
Portstewart Strand sea temperature — next 7 days
Sea temperature varies by under 1.2 °C across the week.
| Date | Sea temp | Range | Suggested wetsuit |
|---|---|---|---|
| Thu 3 Septtoday | 16.5 °C | 16.5–16.6 °C | 4/3 mm full suit |
| Fri 4 Sept | 16.4 °C | 16.4–16.5 °C | 4/3 mm full suit |
| Sat 5 Sept | 16.3 °C | 16.2–16.4 °C | 4/3 mm full suit |
| Sun 6 Sept | 16.3 °C | 16.2–16.4 °C | 4/3 mm full suit |
| Mon 7 Sept | 16.2 °C | 16.2–16.3 °C | 4/3 mm full suit |
| Tue 8 Sept | 16.0 °C | 15.9–16.2 °C | 4/3 mm full suit |
| Wed 9 Sept | 15.6 °C | 15.4–15.8 °C | 4/3 mm full suit |
Figures are modelled sea-surface temperature, not readings from a buoy or a thermometer in the shallows — expect a degree either way, and more in a shallow bay on a hot afternoon. Wetsuit suggestions are general guidance: cold tolerance varies a lot between people, and wind, session length and air temperature matter as much as the water does.
What wetsuit for what sea temperature?
| Sea temperature | Wetsuit | Extras |
|---|---|---|
| 24 °C and above | Boardshorts or swimsuit | — |
| 22–24 °C | Rash vest or 1 mm top | — |
| 19–22 °C | 2 mm shorty or spring suit | — |
| 17–19 °C | 3/2 mm full suit | — |
| 14–17 °CPortstewart Strand today | 4/3 mm full suit | boots on longer sessions |
| 11–14 °C | 5/4 mm full suit | boots and gloves |
| 7–11 °C | 5/4/3 mm hooded full suit | boots and gloves |
| Below 7 °C | 6/5 mm hooded full suit | thick boots and gloves |
Conditions at Portstewart Strand
Water temperature is one input. For wave height, wind and a 0–100 score per sport and ability level, see the full forecast.
Frequently asked questions.
What is the sea temperature at Portstewart Strand today?
The sea at Portstewart Strand, United Kingdom is 16.6 °C today. This is modelled sea-surface temperature rather than a buoy reading, so allow a degree either way.
What wetsuit do I need at Portstewart Strand?
At 16.6 °C, 4/3 mm full suit is the usual choice at Portstewart Strand. A 4/3 keeps a two-hour session comfortable; many people add boots. Most people add boots on longer sessions. Cold tolerance varies, and wind and session length matter as much as the water temperature.
Is the sea warm enough to swim at Portstewart Strand?
At 16.6 °C the sea at Portstewart Strand is swimmable but brisk — fine for a short swim, and most people want a wetsuit for longer.
How much does the sea temperature at Portstewart Strand change over a week?
Over the next 7 days the sea at Portstewart Strand stays between 15.4 °C and 16.6 °C. Open water changes temperature slowly, so it rarely moves much inside a week — seasonal change is what matters.
