Heavy snow has swept across Britain sparking flight cancellations, with drivers being warned of dangerously icy roads.
Temperatures struggled to rise much above freezing as a band of wintry weather hit the UK on Tuesday.
The mercury is expected to plunge to -6C overnight, according to the Met Office.
A yellow weather warning for ice came into force at 4pm on Tuesday and remains in place until 11am on Wednesday, covering much of the country.
Six flights in and out of Manchester Airport were cancelled, affecting hundreds of passengers. Further flights were delayed as staff battled to de-ice aircraft.
In Scotland, flights to Glasgow and Edinburgh from Stornoway Airport were delayed. Three schools were closed in the Highlands.
Travellers faced some disruption as roads were closed due to the icy conditions.
Campaign manager Ally Wilsdon, 25, told the Standard her half hour journey home from Stokenchurch via High Wycombe took three hours.
"It was like Doomsday. There were cars abandoned everywhere," she said.
Light flurries of snow began to fall in parts of west London including in Ruislip.
— Darren Boyle 🇮🇪🇪🇺 (@misterscoop)January 22, 2019
Met Office meteorologist Martin Bowles told the Standard there had been up to 6cm of snowfall in High Wycombe, Buckinghamshire on Tuesday afternoon as the cold snap took hold in the south-east.
Further hail, sleet and snow showers are expected across England, Scotland and Wales overnight and into Wednesday.
Wintry weather affected driving conditions during the morning rush hour on Tuesday.
By mid-morning Police Scotland had received 125 reports of road incidents, with the force urging motorists to slow down and drive to the conditions.
*NEW @metoffice weather warning* 11:00⌚
Another YELLOW weather warning for ICE will be in place from 4pm today until 11am tomorrow ⌚ for all areas affected please check here: https://t.co/5jW2yC5J65
Please drive according to conditions and #StaySafe ❤ pic.twitter.com/PrIyruZqrq— Traffic Scotland (@trafficscotland)January 22, 2019
Traffic Scotland urged drivers to take care on roads.
— Highways England (@HighwaysEAST)January 22, 2019
Highways England has warned of severe delays on the M40 northbound due to the wintry weather conditions in the south-east.
Meanwhile drivers in Buckinghamshire were left stranded as heavy snow brought traffic to a standstill in parts, sparking delays of several hours.
— Omar Smith (@omarsmith)January 22, 2019
Footage showed cars queuing on the A404 between High Wycombe and Amersham.
Drivers were earlier warned of heavy snowfall on the M62 trans-Pennine route as efforts were underway overnight to keep the road open using ploughs and salt.
Mr Bowles said the cold weather was set to continue on Tuesday night across the country with a widespread frost everywhere.
But the forecaster played down reports that Britain was facing the coldest night of winter so far, breaking the current record of -10.8C in Braemar, Aberdeenshire on January 18.
He said: "The lowest temperature is likely to be around -6C, potentially lower on the mountains.
"More widely it will be below freezing and parts of the north-west could drop down to -5C."
Mr Bowles added that the snow is set to continue for the next couple of hours in the south-east and then clear away.
But there will be some showers in Wales and Scotland overnight, he said.
Snow was not confined to the hills in Scotland on Tuesday, with flurries in Edinburgh and Glasgow.
There was also snowfall on the Pennines in the north of England.
The A83 was blocked in Argyll and Bute, while the B974 in Aberdeenshire closed after vehicles got stuck in snow.
Flights to Glasgow and Edinburgh from Stornoway Airport were delayed and three schools were shut in the Highlands due to the weather.
It comes after the Met Office warned that thundersnow could strike the UK this week as temperatures plummet below zero.
Thundersnow is an unusual phenomenon that normally only occurs during a few months of the year.