I think a better question is do YOU have the intellect to keep YOURSELF warm?
I don't know you from the next guy, so I'm in no position to decide whether of now you'd know how to survive for a variable amount of time in a cold climate, but I'm going to give you the benefit of the doubt and say you realize that it takes a lot more to outlast zombies in a cold climate than just a jacket.
For instance, how far north are you going to go? What happens when the zombies thaw out? Are you going to go around when the temperature is around or below it needs to be for an organism (dead or not) to freeze to the point of being frozen solid? If so, how far do you travel from you base camp? Are you willing to risk succumbing to the cold yourself?
Also, like someone said before, there will be other survivors who will also travel north putting a huge strain on already limited resources to sustain human life.
Personally, I don't have much plan in place, but what I would like to do and I think this has the best potential for a comfortable survival. I'd have a sail boat and live off of that in the ocean. I'd try to cultivate a modest garden on board and have some sort of desalinization apparatus with as little parts as possible for a.) reduced risk of wear and tear and b.) little replacement part storage space. I'd think it'd be prudent to, this is before hand, master how to improvise some sort of desalinization apparatus from spare or low important parts from the boat itself.
Obviously, I'd find it important to carry an assorted array of weaponry on board. Rifles, pistols, machete, assorted knives (for protection and to use as tools), blunt instruments (baseball bats, crow bars).
I'd think it also prudent to bring things with multiple uses (such as the sharped edge instruments and crow bars, etc.) as it reduces the amount I'd space I'd need. Also, I'd have a.) a wide band two way radio and either b.) a replacement or two or c.) replacement parts and the knowledge or access to the knowledge of how to repair a busted radio.
I would stay somewhat close to the coastal areas but far enough away to not have to anchor much. If I would ever wish to dock in an area, I'd more than likely stay off shore for a few days to observe the area to develop an educated guess to the level of danger in the surrounding area if I need to go scavenge.
Oh, and I'd try to have a large library of books on board so I don't go TOO crazy. Also, I'd want some companionship but a very small group for various reason.