The hottest month in Imperial Beach is September when the average maximum temperature is 24°, average temperature is 20° and average minimum temperature is 17°.
The coolest month in Imperial Beach is December when the average maximum temperature is 18°, average temperature is 13° and average minimum temperature is 8°.
The longest days in Imperial Beach are in June, with an average of 14.3 hours of daylight per day. December has the shortest days with an average of 10 hours of daylight per day.
The sunniest days in Imperial Beach are in July which has the most hours of sunshine per day with an average of 10.1 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 7.4 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 11.9 and lowest in December when it reaches 3.5.
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 Imperial Beach are found in August when they peak at 30° and lowest in January when they dip to 18°.
The sea is best for swimming between May and December when the temperature is above 24° which is warm and pleasant for relaxing and swimming for long periods.
The wettest month in Imperial Beach is September with 13.9cm of rain and February has the most days of rain with 7.3 days with some rain, a dry time to visit the beach.
The driest month in Imperial Beach is June with 0cm of rain and August has the fewest days of rain with 0.6 days with some rain, an extremely dry time to visit the beach.
The most humid month in Imperial Beach is August with a dew point (an indicator of humidity) of 17° which is OK for most but slightly uncomfortable for some.
The least humid month in Imperial Beach is January with a dew point of 9° which is a bit dry for some.
The most windy month in Imperial Beach is April when the average maximum windspeed is 24kmh and the average wind speed is 11kmh.
The least windy month in Imperial Beach is November when the average maximum windspeed is 21kmh and the average wind speed is 9kmh.