Summer Solstice 2025 Canada Time. The first day of summer, also known as the summer solstice, will occur on saturday, june 21, 2025, at 10:42 pm edt. The summer solstice is the first day of astronomical summer, although the more logical metrological summer begins december 1st / june 1st (depending on hemisphere).

Fall starts at the moment when the sun is directly over the equator, going from north to south: It is around this time of year that the clocks go.