U.S. Air Force Airmen from the 633rd Air Base Wing Legal Office wear cold weather physical training attire while participating in unit pt at Langley Air Force Base, Va., Nov. 14, 2011. Airmen should be aware of the weather, including wind chill and temperatures that will affect surface conditions; this is an easy way to avoid wind burn, difficulty breathing, or slipping on snowy or icy surfaces. (U.S. Air Force photo by Airman 1st Class Kayla Newman/Released)