A 'cyclonic' weather pattern is on its way as the late September sunshine is replaced by a blast of heavy rain which will batter Britain following a final baking weekend.
Met Office forecasters says the warmth most of the country has enjoyed will continue into Saturday and Sunday - but warned 'change is coming'.
The unseasonably warm weather so far this month will soon come to an abrupt end early next week.
But higher than average temperatures will last until Sunday, with colder and much wetter weather not far away.
It has been suggested a seven-day downpour could be coming with 'intense, cyclonic' conditions for some.
Met Office forecaster Nicola Maxey told the Mirror that Brits should make the most of a sunny few days.
She said: "We're not saying 'that's it' for the warm weather this year, but things are about to turn more autumnal, that's for sure.
"It's been a fantastic September but we are likely to see the temperature dip from Monday, with wind and rain.
"There will be a cooler air mass, after some places see 24C this weekend. We are going to see a change and it will return to being the typical conditions we see at this time of the year."
The Met Office states in its latest long-range forecast that a noticeable change in temperatures are imminent.
"A band of blustery, sometimes intense, showers pass over much of the UK through Monday, bringing a noticeable drop in temperatures for the oncoming week as it passes," it read.
"As such, eastern areas are likely to start off warm and fine once patchy mist clears on Monday ahead of this. Breezy winds with the risk of gales for Northern Isles.
"A cyclonic pattern will likely develop from Tuesday and last into October, bringing largely unsettled condition across the UK with a very general northwest to southeast split.
"Showers and long spells of rain towards northern areas with the southeast perhaps seeing drier and sunnier weather.
"However, unsettled weather could still spread south with outbreaks of rain.
"Temperatures near average but may rise slightly towards the end of this period."
They predict temperatures could climb to 23C across the east and south east of England on Saturday afternoon.
Temperatures could be as high as 24C on Sunday in some parts of the south.
Low-pressure systems are expected to move to the UK over the weekend, bringing with them a much more autumnal feel.
