A winter storm system is creating very slippery driving conditions on Highway 2 north of Calgary.

RCMP say conditions are especially hazardous around Red Deer's Gasoline Alley, where crews are responding to multiple vehicles that have gone off the road.

Police are re-routing traffic around a section of Highway 2 northbound, between Gasoline Alley and the 67 street exits.

The highway is also slippery, with poor visibility further south.

"QEII from Calgary to Bowden, all nonessential travel is not recommended at this time due to deteriorating road conditions and visibility because of weather," 511 Alberta tweeted earlier on Friday.

From 10 to 20 centimetres of snow is expected in many areas north of Calgary, including Airdrie, Cochrane, Olds and Sundre, according to Environment Canada.

"Rapidly accumulating snow could make travel difficult over some locations. Visibility may be suddenly reduced at times in heavy snow," the agency said on its website.

"General snowfall amounts will be 10-15 cm, however, locally heavier amounts of 20-25 cm is possible by the time the snow ends this afternoon."

Environment Canada has snowfall warnings in effect for:

Airdrie, Cochrane, Olds, Sundre.

Drumheller, Three Hills.

Red Deer, Innisfail, Ponoka, Stettler.

Rocky Mountain House, Caroline.

Drayton Valley, Devon, Rimbey, Pigeon Lake.

Spruce Grove, Morinville, Mayerthorpe, Evansburg.

Edmonton, St. Albert, Sherwood Park.

Fort Saskatchewan, Vegreville, Redwater, Smoky Lake.

Leduc, Camrose, Wetaskiwin, Tofield.

The Chinook's Edge School Division said schools are closed in Sundre, Carstairs, Cremona, Didsbury, Olds, and Reed Ranch because of the snow.

The weather warnings do not extend as far south as Calgary, which is expected to see just light periods of snow on Friday.

Environment Canada meteorologist Kyle Fougere says chinook winds will see Calgary gradually warm up through next week, with highs near 5 C expected until at least Thursday.

Quickly melting snow can be a challenge for Calgary's 60,000 storm catch basins. The city asks residents to clear ice and snow that's blocking their storm drains to help keep the water flowing, if they can do so safely. Otherwise, people should call 311.