I'm going to be "that guy" for a moment and point out that hopefully when the "s" "h's" the "f" you are home and can load up on whatever you keep in your "just in case" closet.
More than likely, you'll be away, so the knife you get is the one you have on you.
It may be a good idea to keep the tools (knife, multitool and so forth) you'll need in your get-home bag in your car.
Better chance of having them when "it" hits! <img src="/ubbthreads/images/graemlins/thumbup.gif" alt="" />