Summer weather is expected to continue into the weekend, with temperatures set to hit 26C (78.8F) in places on Saturday, forecasters have said.
Autumn is due to begin officially on Monday – but much of the UK will be enjoying the sun right up to the change of seasons.
Friday will bring “almost unbroken sunshine” and it will be “very warm in places”, Sky News forecaster Joanna Robinson said.
She added that Saturday “looks very warm”, with temperatures in the mid-20s in the South and “perhaps for parts of northern Scotland too”.
While most people will have glorious sunshine for the rest of this week, beware the nights and early mornings, which will be chilly before the daylight warms the country up, according to Met Office spokeswoman Nicola Maxey.
And summer’s last gasp, with its hot air, could break on Saturday night, just in time for calendars to mark autumn.
The South West could be the first to experience thunder storms, before they spread across the rest of the country throughout Sunday.
“Next week is looking much more unsettled, Ms Maxey said.
“There is a definite autumnal feel with the sunny days but you are also getting the colder nights.”
But it is not all downhill from Sunday, with Ms Maxey pointing out that it is “not unusual to have warm spells in autumn”.
Astronomical autumn is defined by the Earth’s axis as it orbits around the sun. It officially begins on the date of the autumn equinox, which is 23 September this year.
But forecasters also use the start of September to mark the beginning of meteorological autumn, because that date helps to divide the year into four neat seasons, to track records and trends.
Summer weather is expected to continue into the weekend, with temperatures in the mid 20s celcius (77F) on Saturday, forecasters have said. Autumn is due to begin officially on Monday – but much of the UK will be enjoying the sun right up to the change of seasons.