Generally, San Diego has warm weather year round. The average high temperature in San Diego is around 70 degrees. On some days, the temperature can get as high as 80 degrees.
However, during the winter months, the weather can be very cold, especially in the inland valleys. Lows can drop into the high 40s and low 50s. In fact, the coldest temperature ever recorded in San Diego was 25 degrees. The only times this happened in the past century were during the late 1800s and early 1900s.
Rainfall is generally quite low. On average, less than 12 inches of rain is recorded annually. However, there is significant seasonal variation in the amount of rainfall San Diego receives. Typically, January is the rainiest month of the year in San Diego.
On average, there are 3.5 days in January that see at least 0.04 inches of precipitation. The average rainfall amount is 2.3 inches in February. The drier season starts in April and ends in November.
San Diego also experiences fog and marine layer clouds in May. The ocean waters can get very cold during the winter. The average water temperature in San Diego is around 68 degrees. This water temperature has a 25th to 75th percentile band.
In addition, San Diego receives more remnants of tropical storms than anywhere else on the west coast. The remnants of Hurricane Kathleen brought high winds to San Diego. However, the remnants of Hurricane Kathleen are not expected to cause much damage.