Pilot Reported That The Wind Speed At The Airport Had Increased Significantly Since His Departure About 1 Hour Earlier Analysis: The pilot reported that the wind speed at the airport had increased significantly since his departure about 1 hour earlier. He stated that at touchdown, an unexpected strong wind gust lifted the right wing, and the left wingtip contacted the runway. The airplane subsequently veered to the left and collided with an airport sign, which resulted in substantial damage to the engine mount.