San Diego, located on California’s Pacific coast, boasts a mild Mediterranean climate with warm, dry summers and cool, wetter winters. The city is renowned for its stable temperatures, abundant sunshine, and low rainfall, making it an appealing destination for outdoor activities and beachgoers throughout the year.
The best times to travel section shows how the months compare for a visit, so you can find the time of year that fits what you want to do.
Background colours of the months:
The colour shows the typical temperature: yellow (hot), green (mild) and blue (cold). How strong the colour is shows the travel season: full colour means high season, soft colour means shoulder season and soft-striped means off season.
Weather symbols:
Each month has one symbol showing what the weather is typically like, such as hot and sunny, freezing or a rainy or snowy season. Use them to quickly spot months that match the weather you want, or to avoid the ones that don't.
Crowdedness:
The people icon shows how busy the place usually is. The more people, the more crowded it gets.
Additional notes:
The grey info boxes point out special things worth knowing, like recurring weather issues or seasonal events.
San Diego’s climate is shaped by its coastal position and the moderating influence of the Pacific Ocean. Summers (June–September) are warm, dry, and mostly sunny, with average highs of 24–25°C and lows around 18–19°C. Rain is rare in summer, with July and August typically seeing less than 0.1 inches (2 mm) of precipitation. The warmest month is August, with average highs near 25°C, but heatwaves above 32°C are uncommon near the coast. Inland areas can experience higher temperatures, especially during Santa Ana wind events.
Winters (December–February) are cool and wetter, though still mild by most standards. Average highs are 19–20°C and lows around 9–10°C. Rainfall is concentrated in the winter months, with January and February being the wettest (about 50–55 mm per month), but even then, rain is infrequent and usually brief. Snow is virtually unknown. Spring and autumn are transitional, with mild temperatures, low humidity, and abundant sunshine. San Diego enjoys about 3,000 hours of sunshine annually, with the sunniest months from April to October. May and June can bring coastal morning fog (“May Gray” and “June Gloom”), but skies usually clear by midday. Winds are generally light, with occasional stronger breezes during Santa Ana events. The Pacific Ocean keeps water temperatures cool, ranging from 15°C in winter to 20°C in late summer, making swimming most comfortable from July to October.
San Diego’s stable, pleasant weather supports a vibrant outdoor lifestyle, from beach days to hiking and water sports. The city’s climate is a major draw for visitors seeking year-round comfort and sunshine.
| Average climate data for San Diego, United States | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Average maximum temperature (°C) | 18 | 17 | 18 | 19 | 20 | 22 | 24 | 25 | 25 | 23 | 20 | 17 | 25 |
| Average minimum temperature (°C) | 11 | 11 | 12 | 12 | 14 | 15 | 18 | 19 | 18 | 17 | 14 | 12 | 11 |
| Average precipitation (mm) | 27 | 38 | 21 | 17 | 10 | 3 | 13 | 10 | 10 | 8 | 22 | 42 | 220 |
| Average rainfall days (days) | 5 | 6 | 8 | 6 | 6 | 3 | 5 | 4 | 5 | 3 | 5 | 6 | 62 |
| Average relative humidity (%) | 60 | 64 | 67 | 70 | 71 | 74 | 71 | 70 | 67 | 66 | 58 | 61 | 67 |
| Average wind speed (km/h) | 8 | 10 | 10 | 10 | 10 | 9 | 9 | 9 | 9 | 8 | 9 | 9 | 9 |
| Average water temperature (°C) | 15 | 15 | 15 | 16 | 17 | 18 | 19 | 20 | 19 | 18 | 17 | 16 | 17 |
| Average daily daylight hours (h) | 10 | 11 | 12 | 13 | 13 | 14 | 14 | 13 | 12 | 11 | 10 | 10 | 12 |
| Average daily sunshine hours (h) | 6 | 6 | 8 | 10 | 10 | 11 | 11 | 11 | 10 | 8 | 7 | 6 | 9 |
| Average cloud coverage (%) | 21 | 23 | 23 | 21 | 23 | 14 | 10 | 10 | 12 | 13 | 16 | 24 | 17 |
| Average UV index | 4 | 4 | 4 | 5 | 5 | 5 | 6 | 6 | 6 | 5 | 4 | 4 | 5 |
The best time to visit San Diego is from late spring through early autumn (May to October), when temperatures are warm, rain is rare, and the ocean is most inviting for swimming. These months offer the most sunshine and are ideal for beach outings, festivals, and outdoor activities.
The least favourable time to visit is during late winter (January–February), when rain is most likely, though it is still infrequent and mild compared to most destinations. May and June can also be less appealing due to persistent coastal fog, though afternoons are usually sunny.
San Diego’s average highs range from 19°C in winter to 25°C in summer. The coldest month is December or January (highs 19–20°C), and the warmest is August (highs 25°C, lows 19°C).
No, San Diego is quite dry, receiving about 250 mm of rain annually. Most rain falls from December to March, with summer months being almost completely dry.
Extreme temperatures are rare. Days above 32°C are uncommon near the coast, and freezing temperatures are almost unheard of. Inland areas can get hotter, especially during Santa Ana winds.
The best beach weather is from July to October, when ocean temperatures reach 19–20°C and air temperatures are warm. Early summer can be foggy in the mornings but usually clears by midday.
These terms refer to persistent coastal morning fog and overcast skies common in May and June. Skies typically clear by midday, but mornings can be cool and cloudy near the coast.
Pack light clothing, sun protection, and a jumper or jacket for cooler evenings. Bring a rain jacket if visiting in winter, and a wetsuit if you plan to swim outside the summer months.
San Diego enjoys abundant sunshine, with about 3,000 hours per year. The sunniest months are from April to October, while May and June can be cloudier due to coastal fog.
The warmest month, with the highest average maximum temperature, is August (25.3 °C). The month with the lowest average maximum temperature is February (17.2 °C). Overall, the average maximum temperature over the whole year is 20.7 °C.
The month with the highest average minimum temperature is August (18.7 °C). The coldest month, with the lowest average minimum temperature, is February (11 °C). Overall, the average minimum temperature over the whole year is 14.3 °C.
The month with the highest average water temperature is August (20.1 °C). The month with the lowest average water temperature is February (14.7 °C). Overall, the average water temperature over the whole year is 17.2 °C.
The wettest month, with the highest amount of precipitation, is December (42.4 mm). The driest month, with the least amount of precipitation, is June (3 mm). Over the whole year there are 220.2 mm of rainfall on average.
The month with the most days of rain is March (7.7 days). The month with the fewest days of rain is June (2.8 days). Over the whole year there are 62 days of rain on average.
The month with the highest average relative humidity is June (74 %). The month with the lowest average relative humidity is November (58 %). The overall average relative humidity over the whole year is 66.6 %.
The windiest month, with the highest average wind speed, is April (10.3 km/h). The calmest month, with the lowest average wind speed, is October (8.3 km/h). The overall average wind speed over the whole year is 9.1 km/h.
The month with the cloudiest skies, so the highest cloud coverage, is December (24.4 %). The month with the clearest skies, so the lowest cloud coverage, is July (10.1 %). Over the whole year there is an average cloud coverage of 17.5 %.
The month with the longest days, so the most daylight, is June (Average daylight: 14 h). The month with the shortest days, so the least daylight, is December (Average daylight: 10 h). Over the whole year there are 11.9 h of daylight per day on average.
The month with the most sunshine per day is June (Average sunshine: 11.1 h). The month with the least sunshine per day is December (Average sunshine: 6 h). Over the whole year there are 8.7 h of sunlight per day on average.
The months with the highest average UV index are July, August and September (UV index: 6). The months with the lowest average UV index are January, February, March, November and December (UV index: 4). Over the whole year the average UV index is 4.8.
