First Day Summer 2024 Date. Summer 2024 starts on thursday, june 20th in the northern hemisphere, with the first day of summer being the longest daylight day of the year with the earth's axis having reached its furthest tilt and begins to change directiion back. This year's summer solstice will arrive this thursday on june 20 for the northern hemisphere, according to nasa.
The first day of summer in the northern hemisphere will be on june 20, 2024. On that day, the autumnal equinox will occur, marking the beginning of fall.