I'm working in a frozen hellhole this week. Minus 10 on a good day and banked snow everywhere. In a zombie Apocalypse, who has the advantage? The zombies don't need heat or food but they might freeze. The humans are vaguely prepared but now have no heat, light or government in the cold.
Whilst zombies don’t need food etc they also have no Concept of hot and cold. So therefore in sub zero temperatures in theory they would freeze and potentially become Immobile. So therefore would Be easier to Kill
Unfortunately with snow would Mean they would be covered so Greater risk Of Being bitten.
Hope you are watching Praxis Prepper 's current mini series on YouTube. About alien invasion. He also has a running joke about... if I remember... alien zombies bringing bird flu. He also has some useful tips and interesting discussion points about prepping amid all the comedy.