Lived in both areas albeit Colorado a lot longer.
Pros of Washington:
Insane snow falls that are measured in the range of FEET not inches.
Terrain that is some of the gnarliest and most technically fun I've ever encountered.
Meth, lots of meth!
Ski hills not ski resorts
Pros of Colorado:
A bad year here is an average winter anywhere else.
Evidently we're all on Coke too.
Length of season.
Cons of Washington:
Rain, you have to watch where that snow line is. That 3 feet of fresh snow could now be sludge covered with 5 inches of rain on top.
Driving everywhere sucks.
Lack of sun through most of the winter.
The people (subjective I know but seriously fuck 99% of Washington states people)
High suicide rate
Cons of Colorado:
Lower snowfall totals depending on which part of the state.
Terrain that has more rocks exposed than Washington
Idiots that do not know how to drive
It's cold here in the winter (if you are a pussy)
Parking at resorts
Mega resorts vs family ski hills
Vancouver/Pasco is Southern WA so you'll have White Pass or be driving to Oregon. Not exactly an easy straight shot like Colorado has.