First Day Of Summer 2025 Date. (in the southern hemisphere, it is around december 21 or 22.) this date is considered to be the first day. — are you familiar with midsummer day (traditionally june 24) and midsummer eve (june 23)?
When is the first day of summer 2025? — summer begins with the solstice on thursday, june 20, 2025, marking the astronomical first day of summer in the northern hemisphere.