Trout and char fishing in the Tidal Fraser River tends to slow down in the winter months. Most of the fish, which are opportunists, seek for food further upstream by congregating in tributaries where salmon have been spawning. This doesn't mean there are no fish, the fishing would simply be slower if you don't mind standing/sitting idly for a longer period of time.
The fishing generally picks up again in March and April, when eulacheons begin to show up and juvenile salmonids begin to migrate downstream.
Couple of notes for people who have never tried this:
If the trout or char is wild (presence of the adipose fin), it must be released. All bull trout and dolly varden are wild in the Fraser River and its tributaries, as there are no hatchery program for these species. Hatchery cutthroat and rainbow trout are encountered from time to time, they can be identified by the absence of the adipose fin and the presence of a healed scar.
Because it is primarily a catch and release fishery, I personally have avoided using bait when targeting them because too frequently fish are hooked too deeply. Deeply hooked fish usually result in severe bleeding, which increases mortality on fish that are released. This counters the purpose of a catch and release fishery. The use of roe is legal, but it is always good to take in and consider all the information before making a concious decision on the use of it. A couple of things I have done in the past to prevent deep hooking when using roe. A quicker hookset can help. Letting the fish bite on the roe for too long usually results in deep hooking. I've also found bigger hooks (1/0, 2/0) cut down on the chances of deep hooking.
If the water is clear, as it should be for this time of the year, spincasting or flyfishing can be very effective.
I prefer to fish the period between 2 hours before and after flood tide. In the Tidal Fraser, flood tide usually improves water clarity as clearer saltwater pushes in to mix with the murkier freshwater. The mixing also results in bigger food availability.
Good luck.