What is the summer solstice?

16th June 2020 Last updated at 13:05
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The summer solstice is the longest day of the year, meaning the most hours of sunlight. This year in the Northern Hemisphere it falls on Monday 21 June BBC Weather's Stav Danaos looks at the science behind the phenomenon.


The word solstice comes from the fact the Sun appears to stand still - from the Latin words sol (sun) and sistere (to stand still).

On the summer solstice in the Northern Hemisphere, the Sun will be directly overhead at the Tropic of Cancer.

Around this time, areas of Norway, Finland, Greenland, Alaska and other polar regions experience "midnight sun". And across the Arctic Circle, down to a latitude of 23.5 degrees from the North Pole (matching the Earth's tilt), the Sun does not set at all.

The solstice always occurs between the 20th and 22nd June, and during a leap year it always falls on the 20th. This is because the calendar year doesn't match exactly the time it takes the Earth to orbit the Sun - the calendar is approximately a quarter of a day short, which is why we have leap years, to bring the calendar back in line with the Earth's orbit. Therefore, the exact time of the solstice shifts slightly each year.

While 21st June is the summer solstice in the UK this year, for Australia and countries in the Southern Hemisphere this date marks the winter solstice.

While the summer solstice is the day that has the most hours of sunlight, the UK's weather typically becomes hotter during the second half of the summer. Some of our highest temperatures have been recorded in August.