When Does Summer Start 2024 California. Summer 2024 starts on thursday, june 20th in the northern hemisphere, with the first day of summer being the longest daylight day of the year with the earth's axis having reached its. This year, the first day of fall is sunday, sept.
When is the first day of summer 2024? During the summer solstice, states including california will enjoy the most daylight and shortest night of the year.