Longest Day 2025. Sunrise at 5:11 a.m., sunset at. 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.
The amount of daylight only goes down from hereโฆ.for the next six months (more on that later). In other words, on june solstice it is summer time in the uk, the usa, canada, russia, india, and china and it is the longest day of the year while it is winter time in australia, argentina, chile,.