What Is The 1st Day Of Summer 2024 Calendar. Here are the equinox and solstice dates—plus, answers to common questions. The true solstice will arrive in the northern hemisphere at exactly 4:51 p.m.

Fall begins with the autumnal equinox, sunday, september 22, 2024, 8:44 a.m.  — thursday, june 20 is the official first day of northern astronomical summer for 2024 — summer solstice — which is the longest day of the year for this half of the.