When Is The First Day Of Summer 2025 Usa. Summer 2025 starts on friday, 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 furthest tilt and begins to change directiion back. In the northern hemisphere, it always occurs around june 20 or 21.
365 days a calendar at hand! What day of the week does valentine’s day fall on in 2025?