During the cross-country night flight, the airline transport pilot was on a visual approach to the airport. While descending over water on the left base leg, about 100 ft above the surface, the flight entered instrument meteorological conditions with no forward visibility. The pilot looked outside his left window to gage his height and saw "black waves of water approaching extremely rapidly". He tried to pull back on the yoke to initiate the climb, but the nose wheel contacted the water. The airplane nosed over coming to rest inverted in the ocean water.

The pilot reported that there were no mechanical malfunctions or failures with the airplane that would have precluded normal operation.