First Day Of Summer 2024 Date And Time. In 2024 the summer solstice will occur on thursday 20 june at 21.51 bst (20.51 gmt). When do the seasons start?

After this date, the days start getting “shorter,” i.e., the length of daylight starts to decrease. The first day of summer (june solstice) is when the sun is in its most northern position.