I wouldn't worry about driving back more than living in the RV for 3 winter months. Would the park or wherever you're working help you out with making your RV more weatherproof (skirting) or will they help with the propane cost for trying to keep warm? What about fresh water and dumping? It probably could be done and there are probably Alaskans who do this but think it out carefully.
Driving home probably wouldn't be too bad but you'd have to be prepared to just stop anywhere if the roads get bad. You'd probably want chains on all tires, also.
Is this a good-paying job to want to do this? :) Could they use you at any other time of year?
