When Was The First Day Of Summer 2024 Uk. If you’ve been wondering when summer begins, here is everything we know about the 2024 summer solstice, including its date and significance. Summer begins with the solstice on thursday, june 20, 2024, marking the astronomical first day of summer in the northern hemisphere.

When is it and what causes the longest day. The time its set to happen will be at 9:51pm (gmt).