Hmmm. I live in the Dirty Mitten and it can get pretty cold here, but I never really have a problem getting the temps I want and maintaining them. Do I use more fuel than in warmer months? Sure, but everything does in winter including engines. Try it and see how it goes, you might not need to do anything extra. Are your intakes/exhaust vertical stack types? I think that really helps block out the wind... Mine are, and even in the cold wind I swear my UDS almost cooks as if it's insulated.
UDS'-55&16, Akorn, Bar-B-Q Kettle, Drum Grill, miniWSM, cobweb-covered gasser. I'm JD.