San Diego, CA Weather
San Diego hourly forecast: next 24 hours
Today's high of 71°F (22°C) is about 7°F (4°C) below the typical September high of 78°F (26°C).
Current conditions in detail
San Diego weather tomorrow (Thursday, September 17)
Tomorrow in San Diego looks sunny, with a high of 72° and an overnight low of 67°. Rain is unlikely (7% chance). Winds top out near 11 mph, and the UV index reaches 9 (very high).
San Diego 14-day forecast
About the weather in San Diego
San Diego runs on a dry-summer rhythm: the warmest months are also the driest. June averages 2 mm (0.1 in) while the wet season peaks in January at 2.9 inches (73 mm). Highs range from 64°F (18°C) to 78°F (26°C).
San Diego weather: quick facts
- Hottest month: August - highs near 78°F (26°C)
- Coldest month: January - highs near 64°F (18°C)
- Decade extremes (2015-2024): 98°F (37°C) high · 35°F (2°C) low
- Wettest month: January (6 rainy days) · Sunniest: July (12.4 h sun/day)
- Climate type: semi-arid
- Annual swing: 9°C between the average warmest and coolest month · day to night: 8°C
- Average humidity: 74%
Temperatures through the year
At its warmest, in August, San Diego runs to 78°F (26°C) in the afternoon and back to 66°F (19°C) by dawn. January bottoms out at 64°F (18°C) in daylight, 48°F (9°C) after dark. January is the wettest month at 2.9 inches (73 mm) over 6 days; June is the driest.
Rain, sun and snow
Sunshine averages 10.4 hours a day over the year - sunnier than roughly 78% of the cities we track, peaking in July at 12.4 hours. Between the average August and the average January lie 9°C, a narrower spread than about 78% of the cities we track. Across the gridded 2015-2024 daily record, the highest daily maximum for this location was 98°F (37°C) and the lowest daily minimum 35°F (2°C).
Season by season
Spring (March through May)
Spring in San Diego stays on the cool side of mild, with daytime highs averaging 67°F (19°C) and nights around 54°F (12°C); rain comes on about 14 days over the three months. Daylight is generous - around 10.7 hours of sun a day.
Summer (June through August)
Summer is mild and warm here - highs near 75°F (24°C), nights near 64°F (18°C), and precipitation is sparse, near 13 mm (0.5 in) for the season. Daylight is generous - around 12.0 hours of sun a day.
Fall (September through November)
Fall in San Diego is mild and warm, with daytime highs averaging 75°F (24°C) and nights around 59°F (15°C); precipitation is sparse, near 1.9 inches (49 mm) for the season. Daylight is generous - around 10.0 hours of sun a day.
Winter (December through February)
Winter in San Diego is crisp but comfortable, with daytime highs averaging 64°F (18°C) and nights around 48°F (9°C); rain comes on about 16 days over the three months.
Average temperatures in San Diego by month
| Month | High | Low | Rain days | Precipitation | Sunshine | Humidity |
|---|---|---|---|---|---|---|
| January | 64° | 48° | 6 | 2.9 in | 8.6 h/day | 73% |
| February | 65° | 48° | 5 | 2.1 in | 9.3 h/day | 70% |
| March | 65° | 51° | 8 | 2.2 in | 10.2 h/day | 75% |
| April | 68° | 54° | 3 | 0.8 in | 10.9 h/day | 73% |
| May | 68° | 57° | 3 | 0.6 in | 11.0 h/day | 75% |
| June | 72° | 61° | 0 | 0.1 in | 11.9 h/day | 76% |
| July | 76° | 65° | 0 | 0.2 in | 12.4 h/day | 78% |
| August | 78° | 66° | 0 | 0.3 in | 11.7 h/day | 78% |
| September | 78° | 65° | 1 | 0.4 in | 10.7 h/day | 77% |
| October | 76° | 60° | 2 | 0.4 in | 9.9 h/day | 72% |
| November | 70° | 53° | 4 | 1.1 in | 9.4 h/day | 65% |
| December | 64° | 48° | 5 | 2.2 in | 8.3 h/day | 70% |