Punxsutawney Phil is probably the best known ground hog in the world. He has served Punxsutawney, PA since 1887. The general idea is that if the ground hog comes out of his hole and sees his shadow there will be six more weeks of winter, if he does not see his shadow, and stays out for a while, then spring is just around the corner. None of this is scientific of course. February 2nd is traditionally halfway through winter so there will be six more weeks of winter, though they may be milder than those that preceded it.
How to celebrate – Visit Punxsutawney (Either the town or the ground hog) Watch for ground hogs living in your area. Go outside and look for your own shadow, it will do practically the same thing.