ROANOKE, Va. -

Temperatures will stay below freezing until the end of this week, which means road crews face a bigger challenge removing the ice.

The streets and maintenance manager in Roanoke admits this is a challenge, but they're getting there.

According to the City of Roanoke, 97 percent of main roads and 85 percent of secondary roads are clear.

Here's why: There's been a steady stream of salt trucks in and out for the past 24 hours.

These crews are using a special salt with magnesium in it that is especially effective when the temperatures are as low as they are right now.

Salt is more expensive and it's in limited supply, so crews will switch back over to the regular salt once that runs out.

The City of Roanoke asks that if you can get your car off the road it's better for them. Not only will your car not get blocked in when the plows come through, but it won't get damaged if a plow slips and slides.

The Virginia Department of Transportation asks drivers to continue looking out for snow and ice patches on major roads; ice on bridges, overpasses, and shady areas; and snow drifts.