April is a popular month to ask about Semaphore Beach because conditions can shift week to week along this coast. Expect the water near 18.0°C, with daily variation from wind, tides and recent storms. We refresh the live value from Open-Meteo Marine every hour, so the headline above always reflects the current state of the Southern Ocean.
Semaphore Beach sea temperature in April — averages 18.0°C
The sea at Semaphore Beach in Australia averages 18.0°C during April, based on long-run climatology for the Southern Ocean. Use the live reading below for today's actual water and the monthly grid to compare with the rest of the year.
Average sea · April
18.0°C
mild · Good
Live water now
…
Recommended wetsuit
3/2mm fullsuit
At 18.0°C a 3/2mm fullsuit is the standard wetsuit for surfing and watersports.
Monthly comparison
Yes, but expect a fresh dip · Semaphore Beach
Can you swim at Semaphore Beach in June? — 15.0°C water15.0°CCan you swim at Semaphore Beach in July? — 14.0°C water14.0°CCan you swim at Semaphore Beach in August? — 14.0°C water14.0°CCan you swim at Semaphore Beach in September? — 15.0°C water15.0°CCan you swim at Semaphore Beach in October? — 16.0°C water16.0°CCan you swim at Semaphore Beach in November? — 17.0°C water17.0°C
Frequently asked questions
What is the average sea temperature at Semaphore Beach in April?
Semaphore Beach averages 18.0°C in April, based on long-run climatology for the Southern Ocean.
Is the sea warm enough to swim at Semaphore Beach in April?
It is swimmable but fresh; confident swimmers will be fine without a wetsuit.
Do I need a wetsuit at Semaphore Beach in April?
A 2 mm shorty is comfortable for sessions over 30 minutes.