The pilot said that he had obtained a weather briefing before coming to the airport. After completing a preflight inspection of the airplane, he flew to a nearby airport to practice landings. He reported flying over the airfield to observe the windsock, which indicated a wind he estimated to be out of the north about 5 knots. The pilot flew a right traffic pattern to runway 25. While on final approach, he noticed the windsock start to "whip," and he used ailerons to stop the airplane's southerly drift. He said the airplane started bouncing around as he approached touchdown. Immediately after touchdown, the airplane veered left (south) off the asphalt and into a freshly plowed field. The airplane's nose wheel dug into the soft soil and the airplane nosed over and came to rest inverted. The airplane's right wing lift strut was bent, both wings were wrinkled, the aft empennage was bent and wrinkled on the bottom, and the vertical stabilizer was bent. At 1705, the reported winds at Hanford, Washington, bearing 225 degrees at 18 nautical miles from the accident site, were from 340 degrees at 9 knots.