I know that our RH is probably 20-30% lower then yours, but I have never had an issue with it. Have never really had anyone say that it has been a problem in areas that are high. If you are not storing them for 2-3 years, you should be OK. You might consider buying some cheap plastic trash cans like I did and dumping them in those. Mind hold about 200lbs each and last for about a year, and I see no degradation!