My DW and I are leaving the Vancouver, BC area between Christmas and New Years, picking up our MADP in Coburg, Oregon and heading south to Las Vegas and then on to Quartzsite and other Arizona locations for the remainder of the winter.
Our plan is to watch the weather and follow plan A, B or C.
A: If the road conditions look good we'll depart from Coburg down I-5 the 320 miles to Redding, CA in a single day. That should put us south of the higher elevation and related weather issues.
B: If the weather is questionable along I-5 we'll backtrack to Corvallis and head over to the Newport on Hwy-20. We'll then take 101 south to the Bay area. This route adds about 200 miles to our trip over slower roads and forces to navigate through the heavy Bay area traffic. On the positive, the weather is traditionally milder along the coast and snow is far less likely.
C: If weather does not look promising along route A or B then we'll hunker down and wait for the roads to improves and hopefully still hit the time window for CES in Las Vegas.
As OLYLEN said, if you want a good place to stay along I-5, north of the mountains, Seven Feathers RV Resort (operated by Seven Feathers Casino) in Canyonville is one of the nicest parks my DW and I have stayed in recently. There rates are not cheap but with Good Sam and their own loyalty card program (free) the rate drops to under $40. Their loyalty card is acquired at the casino and also provides a $0.03/gal discount on fuel at their truck stop. Their diesel prices were the lowest we saw while going through Oregon and their discount just makes it better. They have a free 24/7 shuttle service to the casino and more and a beautiful indoor swimming pool. If we have to wait out the weather, we'll be doing it at Seven Feathers.
If you had considered going to Grants pass and then taking Hwy 199 over to Crescent City on the coast, be aware that there is a length restriction on that Hwy.
Also, thanks to those who mentioned the chain requirement. I'll likely order a set from Amazon in the next few days to have them onboard. A quick check on Amazon shows cable chains in my tire size (295/80 22.5) available for $115 with free shipping. As I would be buying them solely to satisfy the legal requirement, but not actually use them, price has a greater bearing than quality.
Good luck on your trip.
Retired and livin' the RV dream!
2005 Newmar 43 ft. MADP, Cummins ISL 400HP, 2008 Honda CR-V toad