South Australia is a coastal area of Australia on the Southern Ocean, with 23 tracked beaches. The sea here ranges from about 15°C in the coolest month to 22°C at the summer peak, with roughly 5 months a year sitting above 20°C — the level most swimmers describe as pleasant without a wetsuit. Use the beach list below to check the current sea temperature at each spot before you head out.
South Australia
23 tracked beaches in South Australia, Australia, with live Southern Ocean temperatures.
Sea
Southern Ocean
Avg sea temp now
15.2°C
Best months
November – March
Best time to swim in South Australia
The sea in South Australia peaks in February, when the water averages around 21°C.
The main swimming season runs from January – March, when surface temperatures stay comfortable for extended sessions.
On average, 3 months a year sit above 20°C — the threshold most swimmers describe as pleasant without a wetsuit.
Shoulder months like December and April are noticeably cooler but often quieter, with fewer crowds and steadier weather.
Outside peak season the water drops toward 14°C, so a 3/2mm shorty or full wetsuit makes long swims much more comfortable.
The coldest month is typically July at around 14°C, when cold-water swimmers dominate the coast.
South Australia sits in the Southern Hemisphere, so the warmest sea coincides with the December–February summer and the coolest with July–August.
South Australia sea temperature history
Long-term climatology for South Australia shows an annual mean sea temperature of 17°C, ranging from 14°C in winter to 21°C at the summer peak.
The seasonal swing is roughly 7°C between the coldest and warmest month — a useful yardstick when comparing years or checking whether the current sea is running above or below average.
Recent decades have trended slightly warmer at South Australia, in line with regional sea-surface temperature records for the wider basin.
Monthly averages below are drawn from multi-decadal climatology and are updated as new observations arrive.
Jan
20°C
Feb
21°C
Mar
20°C
Apr
18°C
May
17°C
Jun
15°C
Jul
14°C
Aug
14°C
Sep
15°C
Oct
16°C
Nov
17°C
Dec
19°C
Values are area averages; individual beaches vary by exposure and depth.
South Australia sea temperature: frequently asked questions
What is the warmest month to swim in South Australia?
February is the warmest month in South Australia, when the sea averages about 21°C. Late-season warmth often persists a few weeks after peak.
When is the sea coldest in South Australia?
The coldest month in South Australia is typically July, when the water averages around 14°C. Cold-water swimmers and surfers dominate this period.
When can you swim in South Australia without a wetsuit?
The main swimming season in South Australia runs from January – March — about 3 months a year when the sea sits above 20°C, the level most swimmers describe as pleasant without a wetsuit.
Do I need a wetsuit in South Australia?
Outside peak summer the water in South Australia drops toward 14°C, so a 3/2mm shorty or full wetsuit makes long swims much more comfortable. In peak months most swimmers go without.
What is the average sea temperature in South Australia?
The long-term annual mean sea temperature in South Australia is about 17°C, based on multi-decadal climatology of the surrounding waters.
How do I check the current sea temperature in South Australia?
The live reading at the top of this page shows the current sea temperature in South Australia, updated hourly from marine buoy and satellite data. The 7-day forecast covers water, air, waves, wind and UV for the week ahead.
Beaches in the South Australia
Ranked by current live sea temperature.
- 1Brighton Beach SAAdelaide, Australia15.7°C
- 2Port Noarlunga BeachPort Noarlunga, Australia15.7°C
- 3Glenelg BeachAdelaide, Australia15.6°C
- 4Grange BeachAdelaide, Australia15.5°C
- 5Victor Harbor BeachVictor Harbor, Australia15.4°C
- 6Stokes BayKangaroo Island, Australia15.4°C
- 7Second Valley BeachSecond Valley, Australia15.4°C
- 8Henley BeachAdelaide, Australia15.3°C
- 9Semaphore BeachAdelaide, Australia15.3°C
- 10Somerton BeachAdelaide, Australia15.3°C
- 11Christies BeachChristies Beach, Australia15.3°C
- 12Horseshoe Bay Pt ElliotPort Elliot, Australia15.2°C
- 13Rapid Bay BeachRapid Bay, Australia15.2°C
- 14Middleton Beach SAMiddleton, Australia15.2°C
- 15Maslin BeachMaslin Beach, Australia15.0°C
- 16Emu BayKangaroo Island, Australia15.0°C
- 17Largs BayAdelaide, Australia14.9°C
- 18Aldinga BeachAldinga, Australia14.9°C
- 19Vivonne BayKangaroo Island, Australia14.9°C
- 20Sellicks BeachSellicks Beach, Australia14.8°C
- 21West BeachAdelaide, Australia14.6°C
- 22Horseshoe Bay SAPort Elliot, Australia14.6°C
- 23Port WillungaPort Willunga, Australia14.4°C
Swimming in the South Australia — FAQ
How warm is the sea in the South Australia in September?
The Southern Ocean off the South Australia averages about 15.0°C in September, based on long-term monthly averages for this coast.
When is the best time to swim in the South Australia?
The South Australia is warmest in February (around 21.0°C) and coldest in July (around 14.0°C). There are typically 0 months a year when the water sits above 22°C.
What is the average yearly sea temperature in the South Australia?
Across all twelve months, the sea in the South Australia averages about 17.2°C.
Do you need a wetsuit to swim in the South Australia?
The sea in the South Australia stays below 22°C even at its warmest (~21.0°C in February), so a 3/2mm or thicker wetsuit is recommended for longer swims year-round.