First Day Of Summer 20254 2025. 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. The data correspond to the seasons of the year 2025.

Click on the date that interests you to see the lighting map of the earth on that date and time (beginning of the season). 36 rows in the northern hemisphere, it always occurs around june 20 or 21.