Hundreds of schools are closed in Scotland and Wales as police advise motorists in affected areas to drive with caution.
The Met Office has issued amber weather warnings for Central Scotland, Tayside and Fife, Grampian and the Highlands and Islands.
In Aberdeenshire alone 69 schools are closed while dozens of others are partially open with limited or no school transport running.
A number of roads in north east Scotland were blocked because of heavy snow including the A93 and the A928.
The wintry weather continued to disrupt work and travel across Wales with several hundred school closures and the south east hardest hit.
In the Caerphilly Council area, a total of 91 schools were reported shut due to the adverse weather.
A forecaster for MeteoGroup, the weather division of the Press Association, said: "With more snow coming today, we can expect more disruption.
"This morning we will see up to 10cm in snow in Scotland, northern England and around 2cm in East Anglia followed by more snow this evening in southern England - maybe up to 6cm.
"Temperatures were very low overnight, as low as -11.3 in Buckinghamshire, and will be low again tonight with many places struggling to stay above freezing during the day.
"The rest of the week will see widespread frost and showers."
Latest forecast from Weather Presenter, Liam Dutton:
During the rest of Tuesday, heavy snow will gradually ease across eastern Scotland, but not before another 2-5cm falls in places.
At the other end of the UK, south Wales, the West Country and southern parts of England will see a band of persistent snow arrive during Tuesday afternoon, making for a difficult evening commute.
2-5cm of could fall, with as much as 10cm across the hills, mountains and moors. The snow is also likely to be wet, with big flakes falling, making visibility very poor.
This snow will then drift northwards overnight into the Midlands and north east Wales, where again, 2-5cm can be expected widely.
With temperatures struggling to get much above freezing by day and falling well below at night, ice will be a widespread problem across the UK in the coming days - especially on untreated roads and pavements.
Snow map: latest news and weather updates
Dangerous road conditions
Emergency services in Devon were called to a serious crash on Tuesday morning after several vehicles spun off the main route into Plymouth.
At least one person is seriously ill in the city's Derriford Hospital following the collision on the A38 between the Manadon and Marsh Mills junctions of the Exeter-bound carriageway shortly before 6am.
The AA said it was expecting today to be one of the busiest days for call-outs this winter, at more than 17,000.
Breakdowns were being reported at a rate of around 2,000 an hour with the busiest areas being the Midlands, London, the south west and the south east.