Thanks for all the feedback! Much appreciated! I looked at all the links and it's pretty much what I thought things would look like at that time of year. In case it does get below freezing at night time, is there anything to keep in mind as far as traveling in an RV?
I don't think I can say I have a lot of experience driving in the snow, no. It never snows where we live in Israel. I only had to drive in snow conditions twice, and both times were in the US (crossing a mountain pass in Utah in October, and the Ridge Trail road in Rocky Mountain NP in June). Both were short drives, but enough to whiten my knuckles! I was driving a minivan, no chains or special tires.
I should probably mention that I've never driven an RV, or anything larger than a minivan for that matter. My husband's not very experienced with large vehicles either (though he has some experience with driving military tanks ;) ). Everyone keeps telling me that motorhomes are easy to drive and are fairly stable. With the one-way deal, they can't guarantee a specific model either. It can be anything from 23ft to as large as they rent (40ft?).
I also wonder if 2015 is likely to have more snowfall due to El Ninio. Probably anyone's guess at this stage?
I realize that whether we leave in early April or early May, this is bound to be a huge adventure. We've traveled for over 10 months in the lower 48, with the kids and all. Visited 44 states so far, and spent months in the Rockies and out west. We love mountains, cool weather, nature and long endless roads.
Our other alternative for 2015 is a month's vacation in the Florida area (it's one of the few states we have yet to visit). It's going to be in February, which should be fine for Florida, and just a run-of-the-mill family Florida trip, with the theme parks, the Everglades, beaches etc. No mountains, snow, or long endless empty roads expected there. I'm sure we'll have lots of fun, but there's no doubt my husband and myself prefer an Alaska road trip! An adventure would be awesome. Getting stuck for a couple of days while waiting for them to plow the road would be just fine. What I don't want is to drive at 15MPH because of that for days on end, or worse, end up in a ditch, because the road was icy. Traveling with kids, safety is important to use, even when going out on an adventure.