La Jolla Climate, Weather By Month, Average Temperature (California ...
The hottest month of the year in La Jolla is August, with an average high of 76°F and low of 67°F. The cool season lasts for 4.5 months, from November 29 to April 13, with an average daily high temperature below 67°F. The coldest month of the year in La Jolla is December, with an average low of 51°F and high of 66°F.