Wales has been hit again by snow
Parts of Wales and central England have been affected by heavy snow, and more is predicted for those areas and north-west England overnight.
About 20cm (8in) has already fallen on higher ground in central Wales, and 20-30cm is now forecast in the area.
Severe weather warnings of icy roads have also been issued for Scotland and north eastern England.
Some of the ferry services between Wales and Ireland have been cancelled for Wednesday due to high winds.
The Met Office has issued heavy snow warnings for Wales, the Midlands, north-west England, eastern and southern England, and Yorkshire and Humber.
Severe weather warnings are also in place for icy roads in Central Tayside and Fife, south-west Scotland, Lothian and Borders, Yorkshire and Humber, and north-east England.
Mid-Wales and the Brecon Beacons in the south were worst affected by snow on Tuesday. Most roads managed to stay open, with gritters working around the clock.
The BBC's Wyre Davies, in the Brecon Beacons, said driving conditions in the area were "treacherous".
Passengers planning to travel from Cardiff Airport have been advised to check whether flights are running on schedule.
Scenes such as this in Wales could be repeated
There have also been some snow showers around the Moray Firth and down the east coast to Aberdeenshire.
Train services to and from Glasgow were also affected by the conditions, as were services between Perth and Inverness.
Temperatures plunged to -18C (-0.4F) at Braemar in Aberdeenshire overnight on Monday - the coldest night so far this winter.
New Year's Eve is expected to be cold and dry for most revellers, except east Scotland and north-east England where snow showers have been predicted.
Salt sales soar
Travellers returning to work after the Christmas break suffered a range of problems on Tuesday.
Signalling problems hit train travellers journeying between Bristol Temple Meads and Severn Beach, while emergency engineering work affected services in the Howden area of Yorkshire.
Forecasters say icy roads and pavements are here to stay
More than a dozen planned rail engineering projects led to disruption, but Network Rail said more trains were running over the Christmas and New Year period than in the festive period last year.
By 1500 GMT, the AA had attended about 14,000 breakdowns since midnight and expected the total to exceed 18,000 compared to about 8,500 on an average Tuesday.
The motoring organisation said the busiest areas were northern Scotland, South Wales and Gloucestershire.
The Highways Agency is warnings drivers throughout the UK to take care in the next few days as many roads are likely to be icy.
Ice has been a problem in many parts of the UK over the Christmas period after heavy snow and sub zero temperatures.
Householders have been taking action to clear paths, pavements and roads, with sales of salt soaring in supermarkets.
Morrisons said sales of its 1.5kg (3.5lb) bags of cooking salt have increased by almost 400% compared to the beginning of last week.
While Asda said sales of salt have increased by 300% in the past week.
There has also been a brisk trade in cat litter, which can be used as an alternative to grit, with Sainsbury's reporting a rise of 20% compared to this time last year.
DIY retailer B&Q said it was experiencing an increased demand for wellington boots and shovels, while sales of rock salt soared 900% on the previous week.
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