Experts warn that the Arctic blast predicted for next week could bring chaos to Britain's roads as grit will not work in extreme cold.
According to the Express, road safety experts say grit becomes useless when temperatures plunge as low as minus 16C because rock salt is as effective as anti-freeze down to minus 9C but beyond this fails to prevent ice forming on the road.
The AA warned drivers to be prepared for dangerous driving conditions.
Head of road safety Andrew Howard told the Express: 'As well as grit not working below -9C, drivers should remember if it rains it will be washed away and wind blows it away.
'The most important thing is to be prepared. Make sure cars are in tip-top condition and prepare for very long delays.
'Be aware that if the temperatures do drop to below the point when grit is effective, the roads will be icy.'
Yesterday forecasters warned that Britain faces a 'whiteout' next week with widespread snowfall of up to six inches and temperatures as low as minus 30C in remote northern areas.
Forecaster Helen Chilvers of the Met Office said: 'After a slightly milder weekend it is going to turn much colder next week.
'From Tuesday onwards the East of the UK is at risk of snow which will drift towards the West during the week. Widespread night frosts are expected with temperatures well-below average for the time of year.'
Leon Brown of The Weather Channel told AOL Travel: 'Temperatures may hardly rise above zero next week. This will persist throughout December, across Christmas and New Year, so there is a high chance we will have a white Christmas.'
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