Wasn't aware that Alaska "closed down" even though I lived in rural Alaska for 25+ years. Most of the tourist attractions close and most tourists are gone, but the rest of the state keeps percolating right along in spite of the weather. LOL :)
The first sticking snow of winter, usually arrives in the Nenana area, 65 miles SW of Fairbanks on or about Oct 5. It will still be nice in the Alaska Banana Belt around Anchorage and the lower Mat Su valley, but you have to drive back through the Alaska and Canadian interiors to get back out. This is where you will start hitting the cold at night from about mid September on. We used to park our RV just after the Labor Day Weekend the first week in September. Then it was time to get ready for fall moose and black bear hunting, time to change the aircraft from wheels to skis and make sure the wood yard is full of dry split firewood.
I wouldn't plan to stay much beyond the middle of September, unless I didn't mind driving on snow or having below freezing temps at night. People that drive vehicles in the Interior in the winter time, have to do a lot of special winterizing to their cars so they will start and move. Trackrig grew up in that area of the state so is well versed on the matter. Even though he claims Anchorage, he went to high school in Nenana and moved south later.
At my age now, 71, I have no desire remaining to deal with the rigors of winter time in the Alaska Interior, let the younger folks fight that dragon. It can be a beautiful place in the winter, but like a cobra, no matter how beautiful it is, it is still waiting for a person to make one wrong "oops".
I would tend to use about 30 ft as a length between taking a toad and not. As mentioned there are very few places you can't take a mid size Class C and park it at the tourist attractions or most other places. But that is a real personal preference.
