WeatherArchive / Climate averages / San Diego
San Diego weather by month: climate averages
San Diego averages 63°F (17°C) over the year. August is warmest, with highs around 78°F (25°C); January is coldest, with lows near 47°F (9°C). About 12 inches (298 mm) of precipitation falls on roughly 38 days a year, from 30 years of ERA5 data (1996–2025).
| Month | Avg high | Avg low | Precip. | Days ≥1 mm | Sunshine / day |
|---|---|---|---|---|---|
| January | 17.5°C | 8.6°C | 50.5 mm | 5.2 | 8.9 h |
| February | 17.3°C | 9.1°C | 63.2 mm | 6.3 | 9.3 h |
| March | 17.8°C | 10.3°C | 43.4 mm | 5.8 | 10.8 h |
| April | 19.1°C | 11.8°C | 22.4 mm | 3.9 | 11.6 h |
| May | 20.2°C | 13.7°C | 9.8 mm | 2.1 | 12.2 h |
| June | 21.9°C | 15.2°C | 1.6 mm | 0.5 | 13.0 h |
| July | 24.3°C | 17.4°C | 2.9 mm | 0.5 | 13.2 h |
| August | 25.3°C | 18.2°C | 4.1 mm | 0.7 | 12.4 h |
| September | 25.0°C | 17.7°C | 8.3 mm | 1.2 | 11.4 h |
| October | 23.1°C | 15.1°C | 15.6 mm | 2.4 | 10.4 h |
| November | 20.4°C | 11.6°C | 27.9 mm | 3.5 | 9.5 h |
| December | 17.5°C | 8.9°C | 48.7 mm | 5.5 | 8.6 h |
Record high 1996–2025: 36.6°C on 2020-09-30. Record low: 1.8°C on 2007-01-15.
Source: Open-Meteo Historical Weather API (CC BY 4.0). Values are ERA5 reanalysis model data on a ~9–25 km grid, not readings from a weather station, so a single town’s thermometer can differ by a few degrees and local showers can be missed. Grid cell 32.72, -117.14 at 20 m. For snowfall, humidity and a best-time-to-visit score, open San Diego in the climate tool.
San Diego weather month by month
The wettest month in San Diego is February, averaging 2.5 in (63 mm); the driest is June at 0.1 in (2 mm). February has the most days with at least 1 mm of rain (about 6). July is the sunniest month, with about 13.2 hours of sunshine a day, against 8.6 hours in December. If you like average highs between 64 °F and 82 °F (18–28 °C) with few rainy days, aim for June, July and August.
Planning a particular day? See how often that date was wet or hot over 30 years with the event weather odds, or look up what the weather actually was on any past date in the historical weather archive.
Questions people ask
What is the warmest month in San Diego?
August, with an average daily high of 78°F (25°C) over 1996–2025.
What is the coldest month in San Diego?
January, when nights average about 47°F (9°C).
What is the rainiest month in San Diego?
February has the most precipitation (about 2.5 in (63 mm)), and February has the most rainy days (about 6 days with 1 mm or more). The driest month is June.
How much sunshine does San Diego get?
About 10.9 hours of bright sunshine a day averaged over the year, from 8.6 h in December to 13.2 h in July. Sunshine here is the model’s estimate of hours with direct sun, not hours of daylight.
What is the best month to visit San Diego for mild weather?
By average high between 64 °F and 82 °F (18–28 °C) and the fewest rainy days: June, July, August. Prices, crowds and events are not included.