FWIW the PNW is usually a pretty good bet for early season snow, pretty similar to Whistler, except the base elevation at Stevens, Crystal, Baker, Mt Hood and Bachelor is higher, so if there's enough snow on top, there's also enough snow at the base. The maritime snowfall is great for covering up rocks and brush, and sticks to steeper terrain than CO or UT resorts, so most single blacks and often double blacks are open within a week or two of the rest of the place opening. I have had some fine off-piste skiing in early and mid-December.
That said, the resorts are more locals ski resorts than vacation resorts. And with the CAN/US exchange rates, you might be better sticking to Sun Peaks or elsewhere in BC that has snow at that time.