Explosion plume from the March 8, 2005, eruption of Mount St. Helens.

A small, short-lived explosive event at Mount St. Helens volcano began at approximately 5:25 p.m. PST, March 8, 2005. Airplane pilot reports indicate that the resulting steam-and-ash plume reached an altitude of about 36,000 feet above sea level within a few minutes and drifted downwind to the northeast. The volcano's rim stands at 8,325 feet.  Data and caption by U. S. Geological Survey.