I figured out the correlation of pain and baramoter years before my rhuemy said, "studies have shown that barometric pressure does affect arthritis..." My response, "No kidding sherlock..." (though, 'kidding' was not the choice word at the time.)
The problem is, I never paid attention to WHAT the pressure was to figure out was it LOW or HIGH that triggered me or how to even UNDERSTAND the b. pressure system.
I often felt rain come on up to 48 hours ahead of time - even if the weather didn't seem to change much, somehow I knew something was "in the air" so to speak! Yet, during certain weather conditions, I did NOT feel it come on ahead of time. The heat waves we have here do the same thing....when it gets so dry during them, my joints feel great! But, when it's humid (even a bit) and hot, I'm miserable in the joints.
Does anyone sometimes get those pressure headaches a few hours before it rains? Boy, those are a giveaway as well! At least THAT goes away once the rain comes, the joints, sadly, continue to hurt!
So, my own personal experience would say, it is the pressure itself - not necessarily the cold that brings on the pain, though it doesn't help. **