1) Grab a Cart
2) Bottles of water
3) Large SOG, Gerber or Buck hunting Knife
4) Utility tool (I already keep a Leatherman Wave with its knife on my belt 24/7/365 anyway)
5) Clorox (Water purification)
6) Fine Plastic mesh screen (For Sprouting Seeds)
7) Quart plastic bottle with wide mouth and lid
8) Bunch of seeds for sprouting (natural foods Isle or Pet food isle)
9) Other food stuffs to be eaten for next few days while waiting for the sprouts to happen.
10) Plastic Tarps
11) 550 Cord
12) .22 cal rifle and several large boxes of Hollow Points.
In the event it is suspected Nuclear i would probably then try to either go into the basement of the building, or Underneath the the Tin Sheet Roofing stacks... If that was not possible I would find the best area to hunker down under as much bulky Cement bags etc as I could and try to stay there for at least a week or two.
But if I thought that I was near .. say just a few miles away from an important military base, and that there would be a direct nuclear hit near me... I would do things entirely different... In that case I would quickly climb up onto the roof and watch it with no protection at all... Better to die quickly from the blast.. than to die of radiation sickness weeks later... at long last.