By the sounds of it, Seattle is very similar to Vancouver. We average about two weeks of snow a year - roughly one week in November/December, then another week in January/February. Each time there's only about 3 or so inches of snow. Usually it's not a problem on main roads, but this year we got a little more snow than usual. The zip-ties would come in extremely handy for the several days of on-road-snow we actually have to worry about. For us Pacific Norwesters, $100 studded tires is overkill.