G. L. Pease is as good a source as I need. Check this article out.
"Some years ago, I did a little research to discover where an average tobacco will equilibrate at various relative humidity (RH) levels. This was prompted by some questions as to whether or not pipe tobacco could be stored in a cigar humidor. This isn’t a good idea for a couple of reasons. Tobaccos quickly take on flavors and aromas from their environment, and we don’t want our cigars tasting like pipe blends, or vice versa. And, it turns out that while cigars are happiest in the region of 65-70% RH, a somewhat lower range is more suitable for pipe tobaccos. At an RH of 60%, pipe tobaccos will tend to stabilize near 12% MBW, and by 66% RH, it will find itself approaching 14% MBW. At 70% RH, the tobaccos will go beyond 16% MBW, which, as discussed, is too high for proper smoking. Keep them separate. They’ll both be happier, and so will you."
