There are some B&Bs in the Fairbanks area that tend to specialize in the winter northern lights watching. Forum member, Cleary, AKA Chuck Johnson and his wife, were running such a place. If they have retired, then he could tell you some names to contact.
Most of Interior Alaska tends to be cloudless once the cold of winter settles into the area. Just not enough moisture in the air to form clouds, but as PA12 mentions, that could change on a day to day basis.
Alaska Airlines flies into Fairbanks on a daily basis, but I wouldn't recommend trying to use an RV in winter time Interior Alaska. A car and a B&B or hotel would be the answer. Also consider Chena Hot Springs as a location, about an hour's drive northeast of Fairbanks. I have been at the Bettles Field Lodge in the winter and have seen some outstanding northern lights. No light pollution once you are away from the larger communities.
Forum member, geewizard, who hangs out on the truck camper section at times, is/was an employee of the US Weather Bureau and works out of the U of Alaska in Fairbanks. He would also be a good source of info if you are considering Interior Alaska.
