First Day Of Summer 20234 2025. The first day of summer arrives with the solstice this year on thursday, june 20, 2025 at 4:51 p.m. The first day of summer, also known as the summer solstice, is determined by the earth's tilt and its orbit around the sun.
Spring starts on march 1, summer on june 1, autumn on september 1, and winter on. The first day of summer, also known as the summer solstice, is determined by the earth’s tilt and its orbit around the sun.