On September 1, 1994, at 1916 central daylight time, a Cessna 150M, N66322, was substantially damaged when it nosed over during landing at Mesquite, Texas. The solo student pilot was not injured. Visual meteorological conditions prevailed. The following is based on the pilot/operator report. The pilot was practicing touch and go landings when he observed a storm approaching from the south. He decided to make his next approach to a full stop. He described his final approach as "normal until the wind shifted suddenly" and "the plane reacted violently to the turbulence." The pilot said he was able to land but "the wind blew me off the runway" and the airplane nosed over. He said a flight instructor/witness had told him the "wind had changed suddenly while he was on final approach, and it appeared he had encountered wind shear." The abrupt weather changes were not forecasted.