First Day Of Summer 2025 Canada Usa. In the northern hemisphere, the next summer solstice will take place on june 20, 2025. The first day of summer in the northern hemisphere will be on june 20, 2025.

Summer is arriving a bit earlier than usual this year, and not just because a major heat wave is baking the eastern united states and canada this week. This is the longest day of the year and marks the start of summer in the northern hemisphere.