One year while I was at BYU I was engaged to a girl that lived in Snohomish Co, Wash and I used to drive up to see her on weekends. I'd leave Thurs evening after my last class and drive all night straight through Boise, Baker, LeGrande, Pendleton up through Tri-Cities, Yakima, Ellensburg and then straight in to Seattle. It would take me roughly 15 hrs and I usually hit the morning commuter traffic on I-90 through Snoqualmie Pass into Seattle. I did that during October and November without problems. Beautiful drive.

Getting from I-82 to Pullman might be a little tedious. I used to drive home to Alaska every spring from Provo and back again in the fall and loved the drive even though quite a bit of it through Canada was on 2 lane roads.