Parts of Britain have been placed on amber alert today as the country lies in wait for widespread snow.

The Met Office's severe weather warning, at the second highest level, urges people to be prepared as forecasters warned of up to 15cm of snow.

Sub-zero temperatures are expected in much of the country, with the mercury likely to hit minus 9 across the Midlands.

A temperature of minus 10.6C was recorded in Chesham, Buckinghamshire at 2am, and of minus 10.3C in Benson, Oxfordshire.

Billy Payne, a forecaster with MeteoGroup, the weather division of the Press Association, said: "We will see a frontal system that will push south eastwards across the UK and the rain associated with it will turn to snow.

"There will be some significant accumulations quite widely across much of England. Away from the South West and across eastern parts of Scotland we are looking at 5 to 10cm of snow in many areas.

"And for many parts of northern England, East Anglia and the Midlands we may see up to 15cm in places.

"Wales and the South West along with parts of western Scotland will mostly see rain.

"There will be rain for Northern Ireland as well but I think elsewhere we are looking at risk of snow.

"It should clear away south eastwards by tonight. It will probably clear all but the far South East and East Anglia by dawn tomorrow."

The amber alert applies to Yorkshire and Humber, the West Midlands, East Midlands, east and south west England, as well as London and south-east England, and north-west England.

A yellow alert, which warns people to "be aware", was in place for parts of Scotland, Wales and north-west England.

Much of England is also under a Cold Weather alert of level 3, which warns of "100% probability" of severe cold weather, icy conditions and heavy snow.

The deep freeze has seen daytime temperatures plummet four or five degrees lower than average for February - traditionally the coldest month of the year.

A spokesman for the Local Government Association (LGA) said an army of council staff and volunteers would be braving the elements to make sure vulnerable people were cared for, and residents were also being encouraged to call in on elderly neighbours.

"Motorists are being advised to check the latest weather and gritting updates on council websites and 'gritter Twitter' feeds, as well as refresh themselves on winter driving guidance and what to stock in their car," he said.

"Information about school closures and bin collections is also being updated regularly online.

"Thousands of new grit bins have been placed in estates and side streets, residents have been given their own bags of salt along with salt spreaders in some neighbourhoods, and arrangements have been made with parish councils, community groups, snow wardens and farmers to grit hard-to-reach areas.

"There is no law against people clearing pavements or public spaces. Ministers have repeatedly welcomed public-spiritedness and said common sense, benefit of the doubt in favour of helpfulness and a responsibility on people to tread carefully in slippery conditions should prevail in the face of complaints. Many council websites carry advice on clearing pavements."

British Gas said its fleet of all-weather 4x4s was on standby to get engineers out to customers and keep Britain warm during the cold snap.

A spokesman said the company had received more than 200,000 calls in the last five days, compared with 120,000 to 140,000 during a normal winter week, and was expecting a further 50,000 this weekend, compared with 20,000 normally in the winter.

A spokesman said: "With the roads becoming treacherous across the country, British Gas's fleet of nearly 100 4x4s will help British Gas to meet its customer commitment, to make same-day visits to Homecare customers who have no heating or hot water and report the problem before 1pm."

The Department for Transport said it was now better prepared than ever for severe winter weather.

It said salt stocks across Great Britain stood at more than 2.4 million tonnes - a million more than last year.

A spokeswoman said January 2011 salt stocks were 810,000 tonnes, while January 2012 stocks were 2.497 million tonnes - a 208% increase.

The AA said its patrols attended around double the usual number of breakdowns yesterday.

Areas expected to record snowfall of up to 15cm include Cumbria, Lincolnshire, East Anglia, North Yorkshire, the Peak District and the Midlands.