I have two theories. The fan reset so it's not loud seemed to help, but... this is the weird part... wearing jeans (at least something over bare skin). Though, I don't reccomend fleece (the snuggie) the fan started to run fast when I did that... I immediately took off the snuggie and stopped using my MBP for a few hours. So if you are cold when you use your macbook.... Wear extra layers, just not on your lap.