Kneeteorology - the ability of a knee to predict the weather, esp. following TKR. That's what I have named it. Mine was really reporting yesterday. The barometric pressure was bouncing up and down, although I knew it without checking. My only way to deal with it was to ice, elevate and sleep. Today, the pressure is back up to 30-something and seems to be holding steady. Good thing since I am going out to PT and have errands to run. I've checked on this before but here's a quote from the Arthritis Foundation (arthritis.org.): "Changes in barometric pressure can cause expansion and contraction of tendons, muscles, bones and scar tissues, resulting in pain in the tissues that are affected by arthritis. Low temperatures may also increase the thickness of joint fluids, making them stiffer and perhaps more sensitive to pain during movement." Based on the healing going on inside my knee, that pretty well describes my pain yesterday, even if the arthritis has been removed. Interestingly, knee #1 was okay which confirms the above statement. It is healed up and acts like a healthy knee. So - I hope all of you are having great stable weather, though I worry about the folks up north and their snow storm coming. Is it affecting your new knees? Here's wishing that all of us can stop being kneeteorologists soon!