Niagara falls how to keep budgies warm?

im going to niagara falls on the 25th of december for 2 days and they will be in pak o bird with a fleece cover on they will be inside a hotel but for when there not how will we keep them warm?? winter+niagara falls=COLD because if it snows thats just worser >< we called parrotdise perch its a family store and they know quite a lot about birds they said with pak o bird plus a fleece cover and a couple of blankets or if not blanket then a heating pad they can prob stay warm until we reach the hotel so any ideas on how to plzzzz ..hopefully its not gonna snow that day....