La Jolla is never hot, is rarely cold, and has very low humidity.  Most of us who live in houses here do not have air conditioners, and a few do not have heaters.  It was a shock moving here from the east, where you can expire from the heat in the summers.  Do bring a sweater year round, as the evenings can be very cool, even in the summer.

The best months to come are July through October, when it is generally in the 70s and rarely edging up into the low 80s during the days, and cools to the  low 60's at night, and very, very rarely rains.  November through March are more likely to be rainy, with the peak of the rainy season in January, but we also have some wonderful, sunny, warm days.  April through June are typically the foggy months - May gray and June gloom are what the natives call it.  Often the fog will clear to a glorious day, sometimes early in the day, but one day it finally lifted at 4:15, then rolled back in at 4:30. 

 The weather is nearly perfect, but avoiding the rainy season will make for a much better beach vacation.