Road is Bare
All wheels of a vehicle are on a bare surface. Bare includes:
- Bare and dry: most of the road surface is dry
- Bare and wet: most of the road surface is wet
Road is Partly Covered
Two wheels of a vehicle are on a bare surface. Partly covered includes:
- Partly snow covered: two wheels on bare surface and other wheels likely on loose snow
- Partly snow packed: two wheels on bare surface and other wheels likely on snow bonded with the road
- Partly ice covered: two wheels on bare surface and other wheels likely on ice
Road is Covered
All wheels of a vehicle are on snow or ice. Covered includes:
- Snow covered: all wheels are on loose snow
- Snow packed: all wheels are on snow bonded to road
- Ice covered: all wheels are on ice
