The hottest month in California is September when the average maximum temperature is 24°, average temperature is 19° and average minimum temperature is 14°.
The coolest month in California is January when the average maximum temperature is 17°, average temperature is 12° and average minimum temperature is 7°.
The longest days in California are in June, with an average of 14.5 hours of daylight per day. December has the shortest days with an average of 9.8 hours of daylight per day.
The sunniest days in California are in July which has the most hours of sunshine per day with an average of 10.5 hours of sunshine per day, making it a very sunny and pleasant month with long bright days. December has the least sunshine with an average of 6.2 hours of sunshine per day, making it a quite sunny month with some cloud cover.
The ultraviolet index is the highest in July when it reaches 11.3 and lowest in December when it reaches 2.8.
An ultraviolet index reading above 11 indicates an extreme risk of harm from unprotected sun exposure. Unprotected skin risks burning in less than 10 minutes. Take all precautions because unprotected skin and eyes can burn in minutes. Tanning will be safest before 10am and after 4pm but only with a good application of sun screen. For those with sensitive skin stay in the shade and wear protective clothing, a wide-brimmed hat, and UV-blocking sunglasses. Generously apply broad spectrum SPF 30+ sunscreen every 2 hours, even on cloudy days. Watch out for relections from water that may increase ultraviolet exposure.
The warmest sea water temperatures in California are found in August when they peak at 23° and lowest in March when they dip to 15°.
The sea is best for swimming between June and December when the temperature is above 18° which is cool for swimming, shorty wetsuit may help you extend your time in the water.
The wettest month in California is December with 39.1cm of rain and February has the most days of rain with 10.3 days with some rain, a slightly wet time to visit the beach.
The driest month in California is July with 0.3cm of rain and the least days of rain with 1.1 days with some rain, an extremely dry time to visit the beach.
The most humid month in California is August with a dew point (an indicator of humidity) of 15° which is comfortable for everyone.
The least humid month in California is January with a dew point of 8° which is a bit dry for some.
The most windy month in California is April when the average maximum windspeed is 27kmh and the average wind speed is 11kmh.
The least windy month in California is November when the average maximum windspeed is 21kmh and the average wind speed is 8kmh.