All I can say is that some extra insulation helps when the temps hit -20 or less...
My mom called me yesterday very much in a panic. She had to get to PetsMart quickly. The reason: one of the feral cats she feeds is TOO fat, and she was worried for his health. The cat is BIG. He’s bigger than my mostly indoor kitty and my kitty is fat. I tried to explain to her that it’s good for this outdoor cat, out in the cold (she does have little houses for them to go into), to have the extra fat. He needs the fat and calories in the cold. He thins up every Spring/Summer. She kept insisting that he was going to get diabetes and have health problems. lol. Truth be known, the main reason was she probably just wanted to go out with me, but she does get concerned over the ferals.