Motorists are being urged to use patience as they encounter snow plows and graders cleaning up after this weekend's snowfall.

"First of all, everybody needs to use extreme caution when they're out there," said Mark Allard, Executive Director of Regional Operations for Manitoba Infrastructure. He notes it is especially important when coming up behind a plow truck on the highway, as the machine can create a trail of swirling snow and reduce visibility often to the point of white-out conditions.

"I think a good rule is, if you can't see the mirror on the driver's side because of the snow it is likely that driver can't see you in behind him," said Allard.

He added it is critical to never pass a plow truck on the highway, saying patience is key in allowing operators to safely do their job and notes they will frequently pull over to allow traffic to pass.

Allard explains there are often times where pilot trucks are following multiple snow plows down a highway, covering the entire width of the road. "So once you get past the pilot truck you'd certainly be encountering the back-end of a plow."

He says it is also not a good idea to pass a snow plow on the right-hand side, explaining there is usually a wing of the blade that hangs over the shoulder that pushes snow into the ditch.

But what if you encounter an on-coming machine?

Allard says it is well advised to reduce your speed until both vehicles have gone past each other. "There may be a need where they encroach the centre line to make sure they're getting the majority of the snow off the roadway."