Hundreds of people have been stranded for up to 13 hours due to the winter weather that hit southern Alberta.

The fall snowstorm has affected traffic on the Trans Canada Highway west of Calgary, causing collisions and closures.

Canmore RCMP say the Trans-Canada Highway west of Calgary was closed Tuesday in both directions near Dead Man’s Flats. The westbound lanes opened around 6:20 a.m. but the eastbound lanes remain closed.

Police escorted stranded motorists to the warming centre at the Canmore high school early this morning.

The highway between Calgary and Edmonton was also closed last night after a collision involving more than 20 vehicles.

Parts of Calgary saw up to 40 centimetres of snowfall over 12 hours. People are being told to stay home, and to keep off the roads.

-With files from The Canadian Press.