Snow is forecast above 1,300 metres along the Blueberry-Paulson, a stretch of Highway 3 between Christina Lake and Castlegar.
Snow is expected to begin falling today (Wednesday) until sometime Thursday morning.
The advisory, issued by DriveBC suggests travellers exercise caution and consider alternate plans.
Meantime, Highway 6E is closed in both directions 40 km west of Junction with Highway 23, in Nakusp because of debris on the road.
A geotech crew is on site.
The road is not expected to open for single lane alternating traffic until sometime between 5 p.m. and 8 p.m. Wednesday.
No detour is available.