Don't know specifically about #8, but the Seattle-Everett stretch is notorious for high slide danger in this type of weather. If Amtrak has cancelled Vancouver-Eugene service, it's probably at BNSF's direction so I'd assume that includes the Seattle-Everett piece.

And in the OLD days, they'd have detoured over the Lake Shore line through Woodenville to get the passengers through. On some other lists there's been great discussion about how railroads in pre-Amtrak days would do everything possible to get their passenger trains through in bad weather - there were track section crews every 30 miles or so keeping the line clear, they had alternate routes to use, etc. Now with all the line rationalization and contracting out track support, just shut down the service and wait it out. Sigh...