San Diego weather in May
Temperature, sea and sunshine in May: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in May
Fair
Best time to visit: July – September
What is the weather like in San Diego in May?
In May, San Diego is mild: daytime highs average 20 °C, and nights cool down to about 14 °C. The sea averages 17.4 °C – bracing, so a wetsuit helps for longer swims. With around 10 hours of sunshine a day, there is plenty of sun. It hardly ever rains. All in all, May is a so-so month for a holiday in San Diego.
May compared
How the weather changes from April to June. Tap a month to open it.
More details for May
- Daylight
- 13 h 49 min05:50 – 19:39
- UV index
- 11 · extremeclear sky, noon (estimate)
- Muggy days
- 0 daysdew point 18 °C or more
- Wind
- 17 km/haverage daily peak
- Cloud cover
- 48 %on average
- Hot days
- 0 days30 °C or more
- Time zone
- UTC−7America/Los_Angeles
How the score comes together
- Temperatureweight 35 %18 %
- Seaweight 25 %6 %
- Sunshineweight 20 %100 %
- Few rainy daysweight 20 %100 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Sun, sea & sand”.
What to pack in May
- Wetsuit for longer swims
- Sunscreen
- Sunglasses & sun hat
- A jumper for the evenings
San Diego in May: quick answers
Is San Diego hot in May?
No. In May, San Diego is mild: daytime highs average 20 °C and nights drop to about 14 °C.
Can you swim in San Diego in May?
Only if you don't mind cold water: in May the sea averages just 17.4 °C. Comfortable swimming is possible from July to September.
Does it rain much in San Diego in May?
It hardly ever rains.
San Diego month by month
The whole year in San DiegoAll destinations: USA
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, GeoNames (CC BY 4.0)