Summer 2025 Start Date. In 2025, the summer solstice will occur on june 21, at 02:42 gmt in the northern hemisphere, and on december 21, 2024 at 09:20 gmt in the southern hemisphere. For the year 2024 the meteorological summer will begin on saturday, june 1, 2024 and will end on saturday, august 31, 2024.

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. You can check the spring, fall and winter dates for the years 2024, 2025 and 2026 on our four seasons page.