When Does Summer Officially Start 2024 Canada. Summer begins with the solstice on thursday, june 20, 2024, marking the astronomical first day of summer in the northern hemisphere. When does summer 2024 begin?

Summer begins with the summer solstice, friday, june 20, 2025, 10:42 p.m. Fall starts at the moment when the sun is directly over the equator, going from north to south: