San Diego, CA Weather Forecast & Climate Guide
San Diego boasts a semi-arid Mediterranean climate with mild temperatures year-round. Located on the Pacific coast of Southern California, the city enjoys one of the most stable and pleasant climates in the United States.
Climate type: Semi-arid Mediterranean (Köppen BSk/Csb)
San Diego Climate Overview
Temperatures are remarkably consistent, with summer highs in the mid-70s°F (24°C) and winter highs in the mid-60s°F (18°C). Humidity is generally low, and the city receives only about 10 inches of rain annually, mostly during winter months.
San Diego's weather is dominated by marine influence, creating cool ocean breezes and preventing extreme temperatures. "June Gloom" brings marine layer clouds in late spring and early summer. Fire weather conditions can develop during Santa Ana wind events.
San Diego Weather by Season
spring
Spring is mild and sunny with highs in the 60s-70s°F. The marine layer (May gray) can keep mornings cloudy along the coast, typically clearing by early afternoon.
summer
Summers are San Diego's defining feature — sunny, dry, and perfectly comfortable with highs in the 70s°F at the beach and low 80s°F inland. Humidity stays low and ocean breezes are constant.
fall
Fall brings the warmest weather with September and October often topping summer averages. Santa Ana winds occasionally push temperatures past 90°F and raise wildfire risk.
winter
Winters are mild with highs in the mid-60s°F and lows in the 50s°F. Most of the city's 10 inches of annual rain falls between December and March.
San Diego Average Monthly Temperatures
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| High °F | 66° | 66° | 66° | 68° | 69° | 72° | 76° | 78° | 77° | 74° | 70° | 66° |
| Low °F | 50° | 52° | 54° | 56° | 59° | 62° | 66° | 67° | 65° | 61° | 55° | 50° |
Best Time to Visit San Diego
Honestly, any time — San Diego's climate is remarkably consistent year-round. September and October offer the warmest, driest conditions; March through May is beautiful and less crowded.
Severe Weather Risks
- Wildfires
- Santa Ana winds
- Drought
- Atmospheric rivers
- Coastal fog
Weather Facts About San Diego
- >San Diego has the most stable climate of any major US city — monthly average highs vary only 12°F from January to August.
- >Downtown San Diego has never recorded a temperature below 25°F or above 111°F in 150+ years of records.
- >Annual rainfall is only about 10 inches, making San Diego drier than most of California's coast.
San Diego Weather FAQ
What is the best time of year to visit San Diego?
San Diego is great year-round, but September and October offer the warmest, driest weather with highs in the upper 70s°F and minimal fog. Spring (March-May) is pleasant and less crowded.
Does it rain much in San Diego?
Barely. San Diego averages only about 10 inches of rain per year, almost all between November and April. Summer is essentially dry, and it often goes months without measurable rain.
What is "May gray" and "June gloom"?
A persistent marine layer that forms when cold Pacific water cools moist air into low clouds. Coastal neighborhoods can stay cloudy until late morning or early afternoon for weeks in May and June.
Does San Diego get hot?
Rarely. Coastal highs stay in the 70s°F most of the year. The main exception is Santa Ana wind events in fall, when inland temperatures can briefly push past 100°F.