Well April can still have fog but snow should be gone for most of the trip I'm sure. The thing to remember is if you try to rush it it is so hard to recoup. Our Kids are 11 and 15 and we will be leaving fri April 20th after work (2:00) so we are doing a little bit the first day and then go from there. My hubby does not like to drive 12 hours It makes him tired and the kids get sick of the trip.. so just relax and enjoy the
VACATION.that means the trip down too.

Our drive takes us through the tri Cities then we go down through Redmond OR instead of going to Portland. Some people prefer the Portland route but to each his own.