Any flips in the weather can cause me to flare...I believe its the pressure changes on the cells that cause the pain - either up or down, doesn't matter - any change will cause the effect. The original diagnosis I had, back almost 15 years ago was "Hypersensitive to Gravity" (rather a polite way of saying it was all in my head, don't you think!!!! ) which I interpret as being sensitive to the way that the environment affects your person.
That being said...I have had a marked improvement in reduction of pain since I have been on MSM, which allows the pressure inside the cells to equalize more easily. Its been a 'miracle' for me...I almost feel normal! (except for the days I forget to take the stuff! then, wowzer...'its' back)