Britain is bracing itself for a dramatic change in weather as an “Arctic blast” is expected to sweep across the country this week, according to the Met Office. After a soggy weekend, which saw thunderstorms and weather warnings in London, the arrival of this colder air will send temperatures plummeting.

Following a week where highs reached around 20°C, the BBC Weather service predicts that temperatures in London will struggle to climb beyond 15°C from Wednesday to Friday. The Arctic blast, arriving from Tuesday and Wednesday, will bring even cooler weather and scattered showers, according to reports from the Mail.

Met Office forecaster Craig Snell confirmed the arrival of the cold front, stating, “As we head into Tuesday and Wednesday, cooler air from the Arctic will start to move in, bringing our first real autumn chill of the season.” Daytime temperatures will drop to the mid-teens, while nighttime lows could dip into the single figures.

The Met Office had already issued a yellow weather warning for large parts of the country over the weekend. Many Londoners were awoken by thunderstorms on Sunday morning, with the unsettled weather disrupting plans and causing the cancellation of British Airways flights at Gatwick Airport.

In a statement, the Met Office said, “While some sunshine may develop in the southeast on Sunday, slow-moving thunderstorms are likely.” The yellow warning remained in place until 6 pm on Sunday, with the possibility of an upgrade to amber warnings in more localized areas if severe impacts were expected.

Looking ahead, the cooler temperatures are set to persist throughout the week, with the forecast remaining “unsettled”. As autumn sets in, Britons should prepare for a chillier and wetter week ahead.