Avoid the garage and the basement: typical storage locations like the garage and basement are poor choices for your hardwood. Generally more exposed to dampness or temperature fluctuations, many basements also have ongoing moisture problems (particularly in spring) and an unexpected flood could cause severe damage to the materials.
Good ventilation: Storing hardwood in an area with good ventilation will help prevent humidity build up and condensation. HVAC systems must be in place and in operation 14 days prior, during and after installation of the flooring
Consistent conditions: Particularly on a construction site, a lot of fluctuations can occur; hardwood shouldn't be stored on-site until construction is at a point where heat and humidity can be kept to the same consistent levels as when the house is eventually occupied.
Elevate it: While this is particularly true if you must store the wood over concrete you don’t want condensation to slowly pool under your wood. Be sure to elevate the boxes off the ground using 2x4s or similar objects.