The AA have issued a stark warning to all drives on UK roads, telling people to use "extreme caution" when driving over the weekend.
The AA said anyone heading out in the morning should add extra time and ensure the car is properly roadworthy as conditions were severe.
Spokesman Ian Crowder said on Thursday: "We have got the worst possible conditions really, of fog and icy roads, and that can be lethal.
"I think the message is extreme caution and to prepare for the worst and make sure all windows are clear."
The statement came as a weather warning from the Met office informed drivers to be wary of fog and sub-zero temperatures across England.
The Met Office said "freezing fog" had settled in patches of the country and poor visibility could affect drivers.
17 people were injured in Thame this morning as a Bus overturned on the M40, because of dangerous driving conditions.
Police are investigating and Sgt Mark Scully, of the Hampshire and Thames Valley joint operations unit, said the fog was dense at the time of the crash.
He told Sky News: “We are lucky at the moment we are not dealing with anything considered life-threatening.”
No arrests have been made, a TVP spokesman said.
An investigation into the 20-car crash on the A40 on Wednesday, in which one woman died and many other people were injured, is continuing and there have been no arrests, he said.
A weather warning has been issued urging drivers to be wary of fog and subzero temperatures across large areas of England.
A fog warning had been issued to drivers across swaths of England. The crash happened just 20 miles (32km) from a fatal pile-up on the A40 in Oxfordshire in similarly difficult driving conditions on Wednesday morning.
On Friday morning, Met meteorologist Emma Sillitoe said: "The main thing we have had is large, dense freezing fog patches.
"People driving around in the morning should take care on the roads."
Visibility could be as low as 100 metres and ice could develop on the roads, she added.