Not too likely I'd evac from the PNW because we just don't have the type of crisies I'd evaucate from. But I keep a set of AAA maps and driver's guides for the roads between Washington and Minnesota to the East, and to Arizona to the South in my trunk. Knowing all the roads and the alternative routes might be important, and the AAA guides have a comprehensive lists of all the hotels, campgrounds, gas stations etc etc etc en route. All free to AAA members.

This was before I bought a Garmin GPS or had a smart phone with built in GPS, maps and ability to Bing all the roadside attractions at my thumbs, but suppose those were offline, I'd at least want the paper guides to navigate from after I get past the Cascades. Besides, AAA is a smidge more comprehensive and direct than any online resources, which tend to reward thems that pays them to be listed.

This is not tested but I had an Emergency Manager type mention that driving cross-country in Canada seemed to have better resources in the event we evacuated from the PNW. Provided you can pass across the border, you have far fewer drivers stressing the gasoline supply across the provinces than you might in the States (assuming BC isn't evacuated like our region is). So going North for 2 hours before proceeding East and then heading South to Minnesota and my relatives is a possibility.

FWIW my Toyota Prius has been quite handy in several real world occasions, where the traffic is gridlocked for hours, and someof my fellow drivers are running out of gas idling their engines. The Prius only puts on the gas engine to top off the hybrid battery a bit - you can move 4 miles and everyone but you runs out of gas. Yet you're still stuck either way, because not all the dunderheads have the sense to push their gasless hulks off to the side of the road.