Forecasters have rejected claims they had failed to predict a heavy snowstorm after being blamed by ministers over a night of chaos which left thousands of motorists stranded on Scottish motorways.
Stewart Stevenson, Scotland's Transport minister, said he had not been adequately briefed on the impending storm, and apologised to those stranded for up to 15 hours in temperatures down to minus 17C.
Officials said they had been overwhelmed by the conditions in which grit supplies froze and snow ploughs' blades broke in thick ice.
"We prepared for one set of weather yesterday morning – we had weather greater than we were ready for," Mr Stevenson said.
The Met Office said it was "completely untrue" that it had failed to give adequate warning. It said it had given at least nine hours' notice of the blizzard, thick ice and up to 10cm of snow. Opposition politicians lambasted the Scottish government's apparent failures to warn drivers not to set out.
Police advised against travel last night and said motorists who had abandoned more than 1,000 vehicles should not return to them.
Last night parts of the M8 remained shut and there were warnings of further snowfall and freezing fog. Police were using thermal imaging cameras to see whether anyone was still inside their car.
Worst affected was the M876 near Falkirk, where 650 cars and 350 lorries became stuck on a five-mile stretch. Lorry drivers delivering crisps to Lidl broke open their load to feed motorists trapped on the M8. Those not stuck in the long tailbacks behind jackknifed lorries bedded down at service stations, sharing hotel rooms and sleeping in restaurants. People brought soup and hot drinks to drivers.
Public transport was severely disrupted and a third of Scotland's schools were closed, forcing 200,000 children to miss lessons. But a gradual warming was forecast towards the weekend.