Storm Clouds on Prince Edward Island
November 13, 2004
The photo above showing an impressive looking storm over Prince Edward Island (PEI), Canada was taken on September 1, 2004. After passing through a brief rain storm about 4:00 p.m. (local time), I looked in the rear view mirror of my car and saw ominous storm clouds, the uppermost portion of which appeared to be sunlit. This is referred to as a pileus or cap cloud. These clouds are observed to ascend quite rapidly -- rising at velocities of 40 feet (about 12 m) per second and sometimes even faster. Note the rainbow fragment at lower right.