Flight and Weather
The pilot reported that a pre-flight weather briefing indicated visual flight rules conditions along the route with occasional thunderstorm activity that might require diversion. While approaching St Johns Airport, the pilot observed thunderstorms and overcast clouds ahead and decided to land and wait for the weather to improve.
Approach and Landing
The unicom operator advised that winds favored Runway 20 with a velocity of 20 knots gusting to 25 knots. On final approach, the pilot noted that the winds shifted. Two windsocks at the airport were showing different wind directions. The windsock at the intersection of the runways indicated a wind from 270 degrees, favoring Runway 31. The pilot landed near the centerline of Runway 31.
Accident Sequence
The pilot stated that he was holding controls for the wind when a strong gust got under the left wing and lifted it up. The aircraft then ran off the right side of the runway, entered a ditch, and nosed over.
Additional Details
The wind direction meter in the airport terminal was reported to be inoperative at the time the pilot called for an airport advisory. The demonstrated crosswind component for the aircraft was 15 knots.