First Day Of Summer 20254

First Day Of Summer 20254. The true solstice will arrive in the northern hemisphere at exactly 4:51. The first day of summer is determined by the tilt of the earth's axis as it rotates around the sun.

The summer solstice is the time when the sun reaches its highest and northernmost points in the sky, according to. The first day of summer this year is thursday, june 20, 2024, per the almanac.