Motorists abandoned cars in parts of east Lancashire and Bury
Snow has forced the closure of about 200 schools across north-west England.
Many in Lancashire, Greater Manchester and Cumbria shut due to the heavy falls. Rossendale, Rochdale, Bury, Bolton and Oldham were worst affected.
Up to 4in (10cm) of snow has fallen in some areas, which has led to hazardous driving conditions on roads.
Drivers on the M6, M60, M61 and M62 suffered lengthy delays. Cars were abandoned in north Bury and East Lancashire as roads became gridlocked.
Nearly half of the 110 schools in Oldham were shut.
"Being in the hills, we get lots of snow," an Oldham Council spokeswoman said.
East Lancashire bore the brunt of the school closures in the county - with hundreds of pupils off in the Ribble Valley, Pendle and Rossendale.
Lancashire County Council said its gritters were out overnight across the county's 2,300km (1,429 miles) of roads, but said the salt could not guarantee ice-free highways.
"Following yesterday's forecast of overnight snow our planned action was to carry out a precautionary salting in advance of the snow last night followed by a second treatment after the snow had fallen as necessary," a spokesman said.
"Salt only starts to work when traffic starts to use the road. The action of moving traffic spreads the salt around the highway and helps to melt any ice or snow."
"Although salting is carried out to make the roads safer, motorists should never consider a salted road to be ice-free," he added.
Drivers on the region's motorways have suffered lengthy delays
Cumbria County Council said its entire fleet of 27 gritters had been out overnight.
Two secondary schools - William Howard at Brampton and John Ruskin at Coniston were closed.
Primary schools including Armathwaite, Lazonby, Hayton, Old Hutton near Kendal, Lees Hill near Brampton, Dent near Sedbergh, Shankhill school at Hethersgill and Fir Ends at Kirklinton were shut.
The wintry showers, which started in Scotland and the North of England earlier, will work their way towards the south throughout the day, according to forecasters.
More bad weather is expected overnight on Wednesday into Thursday.
A spokesman for the Department of Children, Schools and Families said it was down to individual schools to make decisions about closures.
"We expect headteachers to take a common sense approach based on the conditions at the school and also the safety of any pupils travelling," he said.
"We will be monitoring the situation day-by-day and we would hope that headteachers can keep schools open while it is safe for them to do so, but decisions about closure have to be taken locally by those who know the local conditions."