CALGARY -- A blast of wintry weather that arrived Monday evening and continued through the overnight hours made for some very difficult driving conditions Tuesday.

The heavy snowfall — with up to 20 centimetres in some parts of the city — has frozen into a thin layer of black ice on some streets as several crashes have already been reported. 

From 5 p.m. Monday to noon Tuesday, Calgary police responded to 128 reported crashes, including 91 non-injury crashes, 13 injury-related crashes and 24 hit-and-runs. 

Police say the number of crashes is typical for a snowstorm of this size, but are reminding motorists to slow down and drive to the conditions. 

Calgary road crews have been out in full force with its full team of graders, sanders and plows working to clear Priority 1 routes first including Glenmore Trail, Crowchild Trail and Macleod Trail. 

Chris McGeachy with Calgary Roads say crews will be applying salt and a pickle mixture to trouble spots such as hills, bridge decks and off-ramps, but drivers should give themselves extra time. 

"We just want to remind people to be careful out there," he said. "Make sure your vehicle is winterized, if you can carry a shovel in your car in a worst case scenario but our crews will be out there to make sure those roads are safe and passable for everyone."

McGeachy adds that the city does not anticipate calling a snow-route parking ban as it expects temperatures to warm in the coming days, but that could change if conditions deteriorate.  

The city’s snow clearing budget is $40 million from Jan 1 to Dec 31 and there is roughly $5 million left for 2020. City officials say the average snowstorm results in a clearing cost of anywhere between $1 million to $1.5 million. 

As for conditions outside of Calgary, Alberta 511 is reporting that the QEII Highway north of the city is partly covered with snow and visibility is low. 

Stretches west of the city on the Trans-Canada Highway to Banff and Lake Louise are covered in ice, as is Highway 2 south of Calgary all the way to Cardston. 

Drivers will need to be prepared to face slick roads and ensure vehicles are winterized as the Alberta Motor Association (AMA) says it will take about six hours for a tow or boost as of Tuesday morning.