When the UK cold snap will end after temperatures plummet to -18°C

For days, the UK has been blanketed in not only snow and ice but also yellow and orange.

Weather warning after weather warning has been issued by the Met Office this week as the wintry weather put Britain at a standstill

Roads and pavements have been coasted with ice, while snow has kept school doors firmly shut and disrupted flights from major airports.

Temperatures sank to -18.7°C last night in the Scottish hamlet of Altnaharra, the chilliest it’s been in 15 years.

Gas supplies are dwindling as Britons try their best to keep warm, suppliers say.

But in the coming days, these snow-ready frigid temperatures are becoming less and less common.

The cold snap might finally be over.

When will it be warm again?

The cold snap kicked off on New Year’s Day, according to the Met Office, with weather warnings issued almost every day since.

There are no more alerts the horizon – for now at least – though most of the country is under a cold-health alert until Tuesday.

Public health officials issue these warnings when freezing conditions are expected to have ‘significant impacts’ on vulnerable people, such as a rise in deaths among the elderly or hospitals becoming frozen stiff.

BBC forecasters say that while the chill will continue tonight, high pressure will swoop in on Sunday and begin to thaw the nation.

We live at the bottom of the atmosphere, and the weight of all that air above us causes pressure. High pressure means warm air flows down and, simply put, blows the clouds away from the area.

The mercury will then slowly climb up as there are fewer clouds to bounce all that sunlight back and forth between the sky and the surface.

‘High pressure will build in across the country with its centre gradually moving to the east of the UK,’ said BBC weather forecaster Stav Danaos.

‘This will bring mild south-westerly winds to all areas by the time we move into next week.’

Some places might still be below freezing going from Sunday night into Monday.

But Scotland and Northern Ireland will likely get back to being toasty by Monday, with the mercury being above average for this month at about 8°C.

Though, flooding may occur as the snow and ice melt, so it’s advised to keep up to date with local flood alerts and warnings from environment officials.

‘The changes in England and Wales will be slower but by around Tuesday milder air should arrive,’ Danaos added.

‘Much like Scotland, local flooding is possible in parts of northern England as snow and ice melts – especially from the Pennines.’

By Wednesday, temperatures will claw out of the negative and be between six and 10°C and remain in the double digits.

The Met Office adds: ‘Temperatures are likely to be generally a little above average, falling to around average into next week, though the south or east may see the odd rather cold start under clear skies and lighter winds.’

Weather officials warn, however, that it won’t be all clear skies.

The northwest is likely to be battered by rain and wind first before making their way across the whole of the UK.

By next weekend, air from the Atlantic will bring about milder, windier weather.

‘This likely leading to bands of rain and periods of stronger winds at times, however, the potential for brief cold northerly spells remains following any deep lows crossing the region, though these brief before a milder westerly likely returns,’ the Met Office adds.

Why has it been so cold recently?

Well, for one, it’s winter. Cold snaps are in no way unusual this time of year.

The world’s weather machine is called the jet stream, a band of powerful winds blowing from west to east about 30,000 feet from the ground.

For the UK, this current sits just to the south. So, between it down there and a stubborn low-pressure system to the east, bitterly cold Arctic air from the north has blasted us for days.

Get in touch with our news team by emailing us at webnews@metro.co.uk.

For more stories like this, check our news page.