San Diego (CA) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit San Diego.
Climate overview of San Diego
Snow and ice are rare in wintertime. The record low temperature was -4°C (25°F). San Diego has on average around 145 sunny days and 115 cloudy days a year. There are an average of 40 days with measurable precipitation.
The best time to visit California and San Diego largely depends on what your destination is and exactly which places you want to visit within the state. For the coastal areas, different travel advice applies than for the Sierra Nevada mountain area or the Death Valley National Park. If you want to take a tour of California visiting all three areas, May, June and September are the best months.
San Diego Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in San Diego - and find the best time to visit.
Monthly Temperature in San Diego
The weather in San Diego changes moderately throughout the year, offering enough variation to appreciate each season. Average daytime temperatures reach a comfortable 26°C (79°F) in September. In December, the coolest month of the year, temperatures drop to a pleasant 19°C (66°F).
At night, temperatures range from around 19°C (66°F) in September to 9°C (48°F) in December.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in San Diego
San Diego has a dry climate with very low precipitation, averaging 226 mm (8.9 in) of rainfall annually. San Diego can be quite wet during December, receiving approximately 59 mm (2.3 in) of precipitation over 7 rainy days.
In contrast, during the driest month (June), you will experience much drier conditions, with 0.4 mm (0.02 in) of precipitation spread across a single rainy day. For more details, please visit our San Diego Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Sunshine Hours in San Diego
San Diego experiences moderate variation in sunshine hours across the seasons. With 10.1 hours daily sunshine in July, it dips to 7.7 hours in February, offering a balanced mix of sunny and overcast days.
Visit our detailed sunshine hours page for more information.
Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
Humidity in San Diego by Month
The relative humidity is high throughout the year in San Diego.
The city experiences its highest humidity in July, reaching 75%. In January, the humidity drops to its lowest level at 64%. What does this mean? Read our detailed page on humidity levels for further details.
Relative humidity over the year
Best Time to Visit San Diego
Monthly ratings reflect general weather comfort, based on daytime temperature and rainfall. Swimming and winter conditions are highlighted separately where relevant.
- Best overall: January, February, March, April, May, June, July, August, September, October and November
- Warmest weather: July, August, September and October
- Most sunshine: July and August
- Fewer rainy days: May, June, July, August and September
- Seasonal pattern: Very little rainfall for most of the year
Frequently asked questions about the climate in San Diego
What is the best time to visit San Diego?
January, February, March, April, May, June, July, August, September, October and November typically offer the most optimal weather in San Diego. In contrast, December tends to have less optimal conditions. San Diego has very little rainfall for most of the year.
What temperatures can I expect in San Diego?
Daytime highs range from 19°C (66°F) in December to 26°C (79°F) in September. Nighttime lows range from 9°C (48°F) to 19°C (66°F).
How much rain does San Diego get?
Annual rainfall is around 226 mm (8.9 in). December is the wettest month with 59 mm (2.3 in), while June is the driest with 0.4 mm (0.02 in).
How sunny is San Diego?
San Diego receives around 3,069 hours of sunshine per year. July is the sunniest month with 304 hours, while February is the cloudiest with just 230 hours. Overall, San Diego enjoys abundant sunshine.
San Diego 3-Day Forecast
San Diego on the map
San Diego is highlighted - select any city to see its climate.
Popular this month
Where to go in August - average daytime high across popular destinations.
Kissimmee
33°C (91°F) Orlando33°C (91°F) Miami Beach32°C (90°F) Destin32°C (90°F) New York City
29°C (84°F) Big Bear Lake
27°C (81°F) Los Angeles
24°C (75°F) San Francisco22°C (72°F) 
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