The climate in La Jolla during September can be summarized as warm, humid and very dry.
September is in the fall / autumn in La Jolla and is typically the 3rd warmest month of the year. Daytime maximum temperatures average around a muggy 26°C (78°F), whilst at night 17°C (63°F) is normal.
| Daytime temperature | 25.7°C 78.2°F |
|---|---|
| Nightly temperature | 17.4°C 63.2°F |
| Average temperature | 21.5°C 70.7°F |
| Daily sunshine | 9.3 hrs |
| Avg rainfall | 4 mm 0.2 ins |
| Rainy days | 1 days |
| Sea temperature | 20.5°C 68.9°F |
| Humidity | 72% |
| Windspeed | 13.3kph 8 mph |
On average September is the 4th driest month of the year in La Jolla with around 4mm 0.2 inches of rain making it a very dry time to visit.
On the flip side this corresponds to an average of 9.3 hours of sunshine per day.
The data used in these monthly averages covers a period of over 100 years right up until last year. As such they are a valid prediction of what to expect for the weather in La Jolla in September 2025.
Best places to visit in September
| Hottest month: | August | 26.1°C 79°F |
|---|---|---|
| Driest month: | July | 1mm 0ins |
| Sunniest month: | January | 8.4hrs |
| Coldest month: | January | 18.4°C 65.1°F |
| Wettest month: | January | 59mm 2.3ins |