When does summer begin in the UK?
The dates and occasions when the seasons change, and why there are two dates
Thunderstorms and colder temperatures have been forecast to mark a cool start to the month when summer begins.
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After record-breaking high temperatures in May, the first week of June is set to mark an end to the heatwave of the last days of spring.
Rebecca Mitchell, senior operational meteorologist at the Met Office, said that there was a “big change on the way”, including rain, possible thunderstorms and strengthening winds.
“The other part of the story is the temperatures will be much lower compared to the week just gone,” she said.
“They’ll be around average for the time of year, which typically is around 17 to 19 degrees in the north and around 18 to 21 degrees in the south, so about 14 degrees lower in some places compared to the previous week.”
But when does summer officially start in the UK?
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When does UK summer begin?
We are now into the first week of meteorological summer, which began on June 1 and will last until August 31, with autumn beginning on September 1.
Meteorologists divide the seasons up according to weather rhythms and the Gregorian calendar, states the Royal Meteorologists Society (RMETS).
But there is also the astronomical calendar, which marks out summer as being from June 21 until September 21, with autumn beginning the next day and lasting until December 21.
June 21 is the longest day of the year and also known as midsummer’s day.
December 21 is the shortest, while day and night are of equal length in the spring equinox in March and autumn equinox in September.
The RMETS added: “Astronomers and others, who concentrate their interests on our solar system, use significant points in our Earth’s orbit around the Sun to define the changes between different seasons.”