U.S. Air Force Capt. Allen Thill, right, assists Senior Airman Timothy Wigton with finding information in an Air Force Instruction manual in Little Falls, Minn., June 12, 2014. Wigton is in the last phase of his upgrade skill training during which he was evaluated on his knowledge of weather. (U.S. Air National Guard photo by Tech. Sgt. Amy M. Lovgren/Released)