In the pilot's written statement he reported that both pilots had planned a round robin cross-country flight from El Monte Airport (EMT), El Monte, California, to Kingman Airport (IGM), Kingman, Arizona, in order to build flight time; they had just both received their private pilot certificates about a month prior to the accident flight. They received weather information from DUAT's and departed EMT at 0600 Pacific daylight time. The flight reached IGM about 0900, they refueled the airplane, and took off about 1345. While at IGM, they checked the winds aloft and noted the winds were from 230 degrees at 25 knots. There were no problems with the flight until Hector VOR, where they said they encountered "severe turbulence." The pilot stated that he was not able to maintain the heading or altitude, and a dust storm was in the area. They decided divert to the Barstow-Daggett Airport (DAG), Daggett, California, and not chance a flight through the Cajon Pass where there was the possibility of severe downdrafts over the mountains. The pilot stated that he checked the ATIS at DAG and noted that the winds were 250 degrees at 34 knots. The tower controller at DAG cleared the pilot to land on runway 26. The landing was normal, and the flight was cleared off the active runway. The pilot taxied the airplane to the taxiway and stopped to look at the "signboard showing [the] directions for parking." At that point the airplane was struck by a strong gust wind and flipped over. The pilot reported that there were no mechanical problems with airplane. According to DAG airport personnel, the winds were from 220 degrees at 35 knots gusting to 50 knots.