Considering Winter in Washington State

We are heading out west from NAS Pensacola in 2018 and we are going to take our time. In preliminary planning it looks like we might only make it as far as Washington State before winter sets in. Is wintering in Washington State (up near Seattle) comfortable. We don't mind cool, even cold occasionally, but would rather not have a snow problem and minimal freezing. Cool to us is 40's, cold is 30's and below. Warm is 70's and hot is 80's. Don't like hot! Wintering in a desert doesn't appeal to us. Any feedback would be greatly appreciated.

We were visiting our daughter in November with the rig near West Seattle. We decided to stay a bit longer than planned and have Thanksgiving with them. Oops - BIG mistake! A huge ice storm came in and froze the RV pipes and water hose. The freeze broke a water pump filter. We had electric, but didn't plan for for a freeze. When we left and headed South, we took the coastal highway to avoid the snowed in passes.

We don't go to the Seattle area beyond October anymore.

You may not like the desert, but we do. Especially the beautiful Arizona desert. We normally spend 3 - 5 months wondering the Arizona desert in winter. Usually, it's nice, sunny weather in the 70's. Some years, it does get cold at night, but rarely a freeze. Definitely no snow. But we also boondock in the desert. No need to pay for an RV park when there's tons of free places to stay. We'll be there again in a few weeks.