Highway 1 is closed in both directions near the Alberta-B.C. border due to a high avalanche risk and may not reopen until Friday afternoon.
DriveBC reports the closure is affecting a 71-kilometre stretch of the Trans-Canada between Golden, B.C., and the border.
It says the estimated time of reopening is Friday at 12 p.m. PT.
Highway 93 in B.C. is also expected to remain closed for a similar duration.
Drivers travelling between B.C. and Alberta can take Highway 16 or Highway 3, which are both open as of Thursday afternoon.
On Wednesday, high avalanche danger closed Highway 16 between Prince Rupert and Terrace.