You have a undefined period of time here, are you leaving Seattle between Christmas and New Years? If you are, I would head south into Arizona and New Mexico from Seattle. Sequoia and Yosemite can have freezes from Oct thru June. I don't mean one overnight, I mean days of freezing. We have been to Bryce NP in April and stayed at Ruby's when they had to plow the campground for six rigs coming in. This May and June we were in AZ, NM an TX and used mostly KOA's, easy to find etc... Places to visit should include, Quartzsite in Jan for show and to see 100,000 or so RVs spread over 18,000 acres of desert with little or no facilities. White Sands, the entire area is interesting, lots of testing of missiles and bombs there in the valley and the Monument is very unusual. Looks like Mammoth in winter(but flat)even the berms look like a snow plow had made them.
Carlsbad Cavers and Guadalupe Mts NPs are fantastic. Lots of open area and lots of developed camping. I forgot about Sonora Desert Natl Mon. Really neat place as is Organ Pipe Natl Mon. I'd save the big ditch for returning home, also Canyon de Chelly Natl Mon(pronounced de shay) and all of Navajoland. Lots and lots of Indian Dwellings that more than rival Mesa Verde NP in CO. Must see there is Hubble's Trading Post. Say hello to Daniel if he is working and to the ladies in the gift store. Most are First Nations People and love their heritage.
Texas is to big for me and takes days of driving to get anywhere.
Going north later in the spring hit Grand Canyon, Page and Lake Powell the Grand Staircase - Escalante Natl Mon and then into Utah for the other Canyons and Arches NP. Don't know what rig you have and what you want except for 50 amp and I don't really know about that. Bryce Cyn NP is not a Canyon at all but is one of the most beautiful of the red rocks area. Zion for us was disappointing, no real handicapped buses. The buses were so jammed that sitting down you can't see anything so if you need to sit, get a handicapped sticker from rangers and drive yourself. You miss the narration but get to see things.
From there it's I-15 south to Orange county and DL. St George has some great areas too and if you want to see Vegas, Oasis RV park has full facilities including a desert oasis type swimming pool. Well at least it has sand around it. I believe it's Valley of Fire St Pk north of Vegas, nice park.
Then from DL going north you can hit Yosemite and Sequoia.
The north rim of the GC NP opens after May 30 so you would probably have to save that for another trip. There is another park in Nevada to see and that's Great Basin NP. It's kind of out of the way but there is a loop from I-15 back to I-15 between Payson UT and Beaver UT.
Now that you're worn out and ready for rain head home.
"I travel not to go anywhere, but to go. I travel for travel's sake. The great affair is to go". R. L. Stevenson
David Bishop
2002 Winnebago Adventurer 32V
2009 GMC Canyon
Roadmaster 5000
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