Treyarnon Bay sea temperature
Sea-surface temperature for Treyarnon Bay, United Kingdom, with the 7-day outlook and what to wear.
What is the sea temperature at Treyarnon Bay today? (3 Sept)
The sea at Treyarnon Bay is 18.5 °C today. A summer full suit is the standard choice at this temperature. The sea and the air are within a degree or so of each other.
Treyarnon Bay sea temperature — next 7 days
Sea temperature varies by under 1.3 °C across the week.
| Date | Sea temp | Range | Suggested wetsuit |
|---|---|---|---|
| Thu 3 Septtoday | 18.5 °C | 18.5–18.6 °C | 3/2 mm full suit |
| Fri 4 Sept | 18.5 °C | 18.4–18.5 °C | 3/2 mm full suit |
| Sat 5 Sept | 18.7 °C | 18.4–19.2 °C | 3/2 mm full suit |
| Sun 6 Sept | 18.7 °C | 18.5–18.8 °C | 3/2 mm full suit |
| Mon 7 Sept | 18.7 °C | 18.6–18.7 °C | 3/2 mm full suit |
| Tue 8 Sept | 18.5 °C | 18.3–18.6 °C | 3/2 mm full suit |
| Wed 9 Sept | 18.0 °C | 17.9–18.2 °C | 3/2 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 °CTreyarnon Bay today | 3/2 mm full suit | — |
| 14–17 °C | 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 Treyarnon Bay
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 Treyarnon Bay today?
The sea at Treyarnon Bay, United Kingdom is 18.5 °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 Treyarnon Bay?
At 18.5 °C, 3/2 mm full suit is the usual choice at Treyarnon Bay. A summer full suit is the standard choice at this temperature. Cold tolerance varies, and wind and session length matter as much as the water temperature.
Is the sea warm enough to swim at Treyarnon Bay?
At 18.5 °C the sea at Treyarnon Bay is swimmable but brisk — fine for a short swim, and most people want a wetsuit for longer.
How much does the sea temperature at Treyarnon Bay change over a week?
Over the next 7 days the sea at Treyarnon Bay stays between 17.9 °C and 19.2 °C. Open water changes temperature slowly, so it rarely moves much inside a week — seasonal change is what matters.
