Incident Summary
A pilot en route observed a developing squall line intersecting the intended route and decided to divert and land. After a normal touchdown, an extremely strong wind burst accompanied by rain pushed the airplane onto the grass off the left side of the runway. The airplane subsequently struck a ditch running perpendicular to the runway before coming to rest nosed over.
Weather Conditions
At the approximate time of the accident, the wind was from 340 degrees at 14 knots with gusts to 30 knots. Visibility was 2 1/2 statute miles with heavy thunderstorms and rain showers. A wind shift occurred with a peak gust of 44 knots.
Sequence of Events
The pilot had obtained a standard weather briefing that included VFR conditions for the intended route. While en route, he saw the squall line and made the decision to divert. Upon landing, the touchdown was normal. Immediately after, an extreme wind gust pushed the aircraft sideways off the runway onto the adjacent grass. The aircraft then hit a ditch perpendicular to the runway, causing it to nose over.
Outcome
The aircraft came to rest inverted after striking the ditch. No further information on occupants or damage is available from the source.