what date summer start
What day is the first day of summer for 2015? Summer begins with the summer solstice on Sunday, June 21, 2015. The exact time of the summer solstice varies upon an individualâs geographical location, but in New York City it will be at 12:39 p.m. EDT. The summer solstice is also known as midsummer, the first day of summer, and the longest day of the year.