Snow and severe weather conditions could hit much of the country

The Highways Agency will monitor temperature on the motorways before sending gritters where they are needed.

A record 1.8 million people are heading abroad for the festive period as the country prepares for a cold snap.

On Saturday four climbers survived an avalanche on Ben Nevis as heavy snow swept across higher ground in Scotland.

The climbers, who suffered a mixture of facial, arm and leg injuries, were airlifted by RAF helicopter to Belford Hospital in Fort William.

Rescuers said they were "very lucky" to have ended up "sitting on top of the snow".

Drivers stranded

Lorries have been fitted with satellite locators and load sensors to keep track of where they are and how fast they are working.

The agency apologised to motorists last winter failing to grit motorways.

CHRISTMAS WEATHER Sunday: Rain in the south-east. Snow on northern hills Monday: Dry, frosty start. Rain turning to snow in the east Tuesday: Cloudy and misty with some rain or drizzle Christmas Eve: Milder but light rain in some parts Christmas Day: Fair day and slightly milder again

The apology came after thousands of drivers were left stranded in freezing weather on the M11 and M25 motorways in the South East of England when snow and ice brought traffic to a standstill in January.

The agency faced criticism from MPs that it was caught out by the sudden falls of heavy snow which left some drivers stuck in their cars overnight.

Now it hopes the new technology will prevent a repeat of the poor communication which left drivers stranded on ungritted roads.

Last month the agency promised drivers the companies it employs to do the gritting will be on standby 24 hours a day, although it admitted there would be no increase in the number of gritting lorries.

The agency is responsible for motorways and major roads while local councils take responsibility responsible for minor routes.

The Highways Agency said it would continue to issue updated traffic information to alert drivers of difficult conditions.

Many road works had been suspended during the Christmas and New Year period.

But the agency warned drivers to take care in the winter conditions, including not trying to overtake gritters and snowploughs on half-cleared lanes.

Forecasters have predicted heavy snow and severe weather in much of the country at the weekend.

Roads packed

Winds gusted at up to 44mph on the south coast of England while snowfalls were expected to spread to southern Scotland some parts of eastern England on Sunday and Monday prompting fears of traffic chaos.

BBC meteorologist Darren Bett told News Online Sunday night would see a "nasty frost" but the weather would gradually get warmer in the run up to Christmas, melting any snow.

The AA estimated as many as 18 million cars would be on the roads at some point over the holiday period.

Some roads such as the M25 could be packed, with 25% more traffic than normal, it said.

Check out the weather forecast, make sure your car is in good condition AA spokesman Richard Freeman Ben Nevis climbers' lucky escape

Even more people would travel on Christmas Eve, whatever the weather, as many would have arranged to meet friends and family, it said.

An AA spokesman said there had been no major problems on Saturday.

But he warned drivers to make sure mobile phones were fully charged and to travel with a shovel in case of snow.

Sunny option

The Association of British Travel Agents said the most popular winter sun destinations for those going abroad this Christmas were the Canary Islands and southern Spain.

For long-haul travellers, the most popular spots were Florida and the Caribbean, while for skiers the top destinations were France, Austria and Italy.