Parts of Britain are bracing for up to 15inches of snow after an Arctic chill swept the country this week.
Storm Bert will strike from Saturday with Britons told to brace for heavy rain, 70mph winds and snow blizzards.
The Met Office has issued snow, ice, wind and rain warnings for all of Scotland, Wales and Northern Ireland as well as for the North, Midlands and South West of England.
The most serious is an amber alert for 1ft 4in (40cm) of snow in northern Scotland on Saturday from 7am until 5pm.
There are warnings rural communities could become cut off, pavements impassable and road delays stranding some vehicles and passengers.
A yellow alert for wind has also been issued down the north-east coast on Saturday with power cuts and travel delays expected.
And a separate yellow warning for up to 5in (150mm) of rain was imposed for most of Wales and parts of Devon and Cornwall from 6am on Saturday until 6am on Sunday.
It comes south-west England saw unprecedented snowfall on Thursday with up to 10in falling in Cornwall - the biggest whiteout in nearly two decades.
SATURDAY: A series of amber and yellow warnings are in place for when Storm Bert hits
A woman and boy go sledging in Aviemore in the Scottish Highlands on Thursday afternoon
Map shows precipitation forecast for Saturday. Grey areas indicate snowfall
Snow falls in the Devon village of Whitestone today as a Met Office warning remains in force
The cold blast caused dozens of schools to close and travel mayhem was also reported with motorists ditching their vehicles and continuing their journeys on foot.
Temperatures have plummeted with the coldest reading this early in the season since 1998 recorded on Tuesday as Braemar in Aberdeenshire fell to -11.2C (12.2F).
Some parts of the country are also already under weather warnings due to the unprecedented weather already this week.
A Met Office yellow warning of snow and ice had been in place across northern Scotland until midday on Thursday, with up to 2in (5cm) of snow expected fairly widely.
A new alert was then issued warning of snow and ice for much of Scotland, northern England and parts of western and eastern England and Wales between midday on Thursday and 10am Friday.
Parts of south-west England including Plymouth and Exeter also received a yellow warning for snow between 5am and 3pm on Thursday, with up to ten inches falling in the region.
Bert is expected to sweep in from the Atlantic on Saturday after undergoing explosive cyclogenesis – a term more commonly known as a weather bomb when the central pressure of a low pressure system falls by more than 24 millibars in 24 hours.
A snow plough clears the A35 road between Dorchester and Bridport in Dorset on Thursday
A snow plough operates through Aviemore in the Scottish Highlands on Thursday
A snowman is used to advertise the Brace of Butchers in Poundbury, Dorset, today
Met Office Deputy Chief Meteorologist Dan Holley said: Storm Bert marks a shift to much milder air and wintry hazards will gradually diminish through the weekend, but heavy snowfall is expected across parts of northern England and Scotland for a time on Saturday, especially over higher ground, and warnings are in place.
Heavy rain through Saturday and Sunday, especially in southern and western parts of the UK, will also bring impacts for some with a number of warnings in place.
We expect 50-75 mm of rainfall quite widely within the warning areas, but in excess of 100 mm is possible over high ground in parts of Wales and southwest England.
He added that rapid melting of lying snow over the weekend and periods of strong winds could bring the potential for travel disruption as well as flooding for some.
Met Office chief meteorologist Matthew Lehnert said: A northerly airflow will continue to feed snow showers into Scotland over the next few days, with this reaching lower levels at times and bringing the potential for some travel disruption.
Overnight temperatures will drop below zero fairly widely over the next few days, which has resulted in some ice warnings, with further warnings likely through this week.
FRIDAY: Snow and ice warnings will remain active for much of the country on Friday
Snow falls in the Devon village of Whitestone on Thursday as a Met Office warning remains in force
Launceston Castle and the surrounding areas in Cornwall are covered in snow on Thursday
A man waits for a bus in Poundbury, Dorset, today as snow falls in the South West of England
A farmer tends to their sheep in the snow amid wintry conditions at Whitestone in Devon on Thursday
An aerial view of snow covering Poundbury on the outskirts of Dorchester in Dorset on Thursday
A sign displays a snow warning at the side of the A9 near Aviemore in the Highlands on Thursday
On Thursday, a mixture of snow, sleet and rain is likely to affect the southwest which could potentially bring disruption.
Its likely high ground in the area will see snow, with a mixture of conditions likely at lower levels. 2-5cm of snow is possible in places at lower levels, with around 10cm possible over higher parts of Dartmoor.