Direct answer
What is the water temperature in San Diego?
Quick answer
San Diego ocean water averages 58–62°F in winter, 64–68°F in early summer, and peaks at 68–72°F in August and September. Most locals wear a wetsuit year-round; comfortable swimming without one is realistic only from roughly late July through early October.
Last updated
Key facts
Month by month
January through April sit in the high 50s to low 60s. May and June warm slowly to the mid 60s despite the cloudy marine layer. July climbs into the upper 60s, and August and September are the two months where the ocean genuinely feels warm.
- Jan–Mar: 58–61°F — full wetsuit
- Apr–Jun: 61–66°F — 3/2mm
- Jul: 66–69°F — spring suit or none
- Aug–Sep: 68–72°F — swimsuit weather
- Oct–Dec: 65 down to 60°F — 3/2mm returns
Where the water runs warmest
Bays beat the open coast. Mission Bay and the Coronado side of Glorietta Bay warm several degrees above ocean beaches, which is why families with young kids gravitate there. La Jolla Shores is the warmest of the true ocean beaches on most days.
Upwelling surprises
A few days each spring, offshore winds pull cold deep water to the surface and temperatures drop 5–8°F overnight even in May. Check a live buoy reading rather than a monthly average before an early-season swim.
Where to see live buoy readings for San Diego
Monthly averages are not today's ocean temperature. For current observations, check NOAA's National Data Buoy Center and UC San Diego's Coastal Data Information Program (CDIP); verify each station's observation time and location because readings can be offshore or outdated. Water temperatures at a shallow bay or sheltered beach may differ. Also consult lifeguard flags and the county's beach water-quality advisories before entering.
- Check the buoy's most recent observation time rather than treating an old reading as current.
- Compare a nearby open-coast buoy with any beach or bay-specific observations available.
- Water temperature alone does not determine swimming safety: check surf, rip currents and county advisories.
Related questions
Can you swim in San Diego in winter?
Yes with a wetsuit. Water sits in the high 50s, which is too cold for most people without one.
Do you need a wetsuit in San Diego in summer?
Not in August or September for short swims. Surfers still often wear a spring suit.
Which San Diego beach has the warmest water?
Mission Bay and Glorietta Bay, followed by La Jolla Shores among ocean beaches.
What is the water temperature in San Diego today?
Check a live source such as NOAA's National Data Buoy Center or UC San Diego's CDIP buoys; temperatures can swing several degrees in a day during spring upwelling.
When is the ocean warmest in San Diego?
August and September, when water typically reaches 68–72°F.
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