The autumn equinox is taking place on Monday, which marks the end of summer and nights are set to become longer than days.
The autumn equinox signals the point when the northern hemisphere begins to tilt away from the Sun, leading to shorter days and cooler temperatures, according to the Met Office.
From this time, nights become longer than days.
The date that astronomical autumn starts can change each year, usually on September 22 or 23, whereas meteorological autumn begins on September 1 and ends on November 30.
Equinox today - ‘equal night’ and day. This photo, just taken, clearly shows the Sun’s shadow perpendicular to the equator. Start of Fall in the north, start of Spring in the south.
— Chris Hadfield (@Cmdr_Hadfield) September 22, 2025
(Image GOES-19 satellite @NOAA)https://t.co/4S8rjqZPqM pic.twitter.com/ZANaxxdQei
During the equinox, the Sun shines directly on the equator, resulting in nearly equal day and night lengths.
More unsettled weather can be expected in autumn, the Met Office said.
Met Office meteorologist Oli Claydon said: “Autumn is what we call a transition season between summer and winter, moving towards typically more unsettled weather, but it doesn’t mean we won’t have spells of what people consider warmer weather.”
This week, the weather is expected to be dry and bright for most of the UK, until the weekend when wind and rain are expected to move in, Mr Claydon said.
There has been below average temperatures over recent days, with low temperatures of minus 2.1C on Sunday night and over a dozen areas below freezing.
But temperatures are expected to be around average this week, with highs of 17 or 18C, the meteorologist added.
