I guess if you want to avoid the conditions you described, you would be much better off to run 5 down to 10. I haven't been to far on 5, but have went all the way across on 90 and 94 from WI. the end of Dec. with just our car. I would not have wanted the 5er behind me on that trip.
You never know when those passes will get dumped on. Mid Mar. is still winter up there.
I traveled on 5 more then I remembered
We went from Portland down to some where around the Bakersfield area, then cut across to AZ.
Not a bad route.
If you want to see the northern route you could do that on the way back maybe.
Edited by: Old Farmer