what is the first day of summer

The first day of summer in 2025 is Friday, June 20. This date corresponds with the summer solstice, which occurs at 10:42 p.m. EDT that day. The summer solstice is when the Earth's axis is tilted most toward the Sun, resulting in the longest day of the year in the Northern Hemisphere. This astronomical event marks the official start of summer. While meteorologists consider June 1 as the start of summer for convenience in recordkeeping, astronomically, summer begins on the solstice, which can occur between June 20 and June 22 each year. The summer solstice is the moment when the Sun reaches its northernmost point directly over the Tropic of Cancer.