I'm looking for thoughts on storing bulk ammo in places that you have no control over the weather and environment. I've always stored all my ammo inside the living area of my house where the temperature and humidity are kept at human comfortable levels.
Contingency planning has me considering alternative and additional locations where I don't have the same control over the environment. Some thoughts include a detached garage or shed, or even a storage facility. It would be out of the weather, but still have the wide variations of temperature and humidity of New England. The ammo would be in a pick up truck bed tool box or similar, either in the original cardboard boxes, and/or ammo cans. The tool box would be off the floor, on 4x4s or the like.
How much of a negative impact would this type of storage have on the ammo? What other options are there that would mitigate those negatives?
Note: Don't be that guy and say, "Store it all at my house"