Met Office warns temperatures to tumble nationwide as ‘Arctic blast’ brings chills

Temperatures had topped around 20C in London last week, with forecasters expecting mercury to hover around 15C for much of this week.

Night-time temperatures will likely fall to as low as 7C on Wednesday as a winterly chill hits the UK.

Met Office forecaster Craig Snell said: “As we go through into Tuesday and Wednesday and beyond, we will start to see even cooler air begin to move in from the Arctic.

“Our first autumn chill of the season is coming our way into the middle part of the week.

“It will bring temperatures around the mid-teens by day and by night, some of us will be falling into the low and mid-single figures.”

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In a statement, the UK’s national weather service also said: “We’re likely to see fresher, cooler temperatures sweeping across the UK, becoming notably cool in the north by mid-week.

“Conditions look to remain generally unsettled during next week, with showers or longer spells of rain at times for most regions, accompanied by blustery winds.”

The drop in mercury is expected to come just hours after a yellow weather warning battered Britain.

Londoners were woken up by thunderstorms on Sunday morning, with dozens of British Airways flights cancelled at Gatwick.

The Met Office said: “Whilst some sunshine is likely to develop in the southeast on Sunday, further slow-moving thunderstorms are likely.

“This yellow warning is in place until 6pm on Sunday and it is possible that further updates to warnings may be issued during that time, including escalation to amber on a more localised scale if confidence in impacts occurring increases.”

England’s Environment Agency issued 24 flood alerts yesterday.

However, only one alert covering Tern and Perry catchments in Walcot and Rodington remains in place.