The Vikings won't be acclimated either. They have yet to have temps like that this winter and it doesn't really get cold until tonight. Getting out there early won't help the Seahawks, but already being out there won't help the Vikings either.
One of the biggest advantages Wilson has as a QB is the size of his hands. I'm sure he'll be protecting them as much as possible.
Anything can happen in the NFL as we know, but ultimately if the Seahawks play as well as they can play, there is no team in the NFL that can hang with them. They simply have the best combination of roster and system. They can win 17-6 (my prediction) and be in absolute control from about mid 2nd quarter onward. Plus they'll have the added benefit of putting this on their extensive list of obstacles to overcome this season. It'll make them even tougher for the Cams to beat.