I was surprised. Compared to other areas in the north Missoula didn't get all that cold. Appears to be more moisture though. Last year -14 F was lowest. Many areas in the north were -20 to -25 F for several days. That said, certainly not RV weather. Brave experienced winter RV people in MT, SD, ND, WY put straw around their RVs. I prefer to be in a warm S&B.
BTW: -14F doesn't account for wind chill factor for those that step outside. -50 to -60F is not uncommon. I would recommend Carhartt bibs, coat, a ski mask, goggles, and good insulated boots. Just to be prepared. You'll only need them on bad days.