For those dealing with active joint issues such as arthritis or poor circulation/accumulation of fluids in joint - there is a plausible explanation as to why they indicate their joint pain increases prior to the coming of bad weather. When pressure drops in the atmosphere, tissues in the body will expand. For those with healthy joint, the effect is practically non-existent. For those dealing with active joint issues, any increase in expansion of weakened and damaged tissues WILL produce an effect. That person will experience some minor aches along with a minor increase in swelling. Back in 2007, Tufts University made the connection between weather changes and an increase in discomfort for those dealing with cases of knee osteoarthritis.