First Day Of Summer 2024 Usa. It marks the start of the summer season in the northern. Overview of holidays and many observances in the united states during the year 2024.
When is first day of summer in 2024 is thursday, june 20, and it lasts until sunday, september 22, inclusive. The summer solstice, or the day with the longest daylight hours of the year, will happen on june 20, 2024.