The pilot stated that during the takeoff roll in the tailwheel-equipped airplane, just after he raised the tail to a level attitude, the airplane yawed slightly to the right. As the pilot was correcting for the right yaw, an “extreme wind gust” struck the airplane, and the airplane pitched nose-up and began to roll left. Despite the pilot’s efforts to regain directional control, the airplane departed the left side of the runway into a bean field where it nosed over. The airplane came to rest inverted, which resulted in substantial damage to both wings and the vertical stabilizer. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation. He further stated that the accident would have been avoided if he had delayed his departure until the approaching weather system had passed. Weather radar data revealed that at the time of the accident a line of thunderstorms, associated with a front, were approaching the airport from the west and were observed over the airport about 8 minutes after the accident. The recorded wind at the time of the accident was from 320 degrees at 23 knots with a peak wind of 27 knots.