Even if they wear coats they would still freeze solid due to the fact they have no body heat for the coat to insulate

Read "World War Z" they would freeze in winter and thaw out in spring and summer.

Well we'd be okay up here then--too damn cold come Halloween! they'd be lucky if they could roll over.

Well, I've wondered about vampires. If they aren't metabolizing anything, where does the blood go when they drink it? eventually the stomach would rupture, so it must go somewhere. Where?

From the Stanford Encyclopedia of Philosophy:

Zombies are exactly like us in all physical respects but have no
conscious experiences: by definition there is ‘nothing it is
like’ to be a zombie. Yet zombies behave like us, and some even
spend a lot of time discussing consciousness. This disconcerting
fantasy helps to make the problem of phenomenal consciousness vivid,
especially as a problem for physicalism. link

With zombies, the only real variation is whether they run or stumble after people, but it's fairly constant that they're dead. So yeah it makes sense they'd freeze in winter.

Whereas Zombification in movies is usually caused by some kind of virus or contaminant, vampires are usually supernatural in nature. Vampires I think require quite a bit more suspension of disbelief, since vampire lore varies wildly. As far as 30 Days of Night is concerned, perhaps when vampires drink blood it does ignite their metabolism so as to create body heat for a while? Just a thought. Or maybe their supernaturalness just magically prevents freezing... who knows?

Also, 30 Days of Night sucked. Muah ha ha ha ha!

@ Willhelm: