Well I’m assuming pretty much everything freezes at some point in temp and I think that goes for the human body to. So if it was just me I’d go north as fast and soon as possible.
But for ppl like me the ones that don’t poses firearms or are not allowed to I would not suggest going near any military instillation's or outposts. Do to the fact that if this country was in deep shit from a epidemic like this I do believe marshal law will be put in effect.
Witch will give Law enforcement and troops on the ground the right to shoot and kill on sight for possessing Arms and looting and verity of other reasons.

Anyways….. Like I was saying for ppl that may be in my position the car may be you’re beast bet. I know in Special Forces they tell there troops to stay mobile and keep communications.