Weather definitely affects my fiancee at times. I did some research and came across this article:

http://www.rsds.org/pdfsall/Weather%20changes-CRPS.pdf

in which changes in the negative to positive ion concentration are implicated as part of the reason why weather changes affect folks with CRPS and other inflammatory diseases. We've tried the negative ion generator and it certainly works for my fiancee, although we haven't been using it recently as she is more or less in remission.