La Plata Tornado

May 10, 2002


Referred by: National Weather Service Forecast Office Baltimore/Washington, NOAA
Summary authors & editors: Jim Foster

The top photo, taken by Ted Dutcher on April 28, shows the La Plata tornado that severely damaged La Plata, Maryland and other towns and communities in southern Maryland and on Maryland's eastern shore. On this picture, the twister is moving east across the Chesapeake Bay. When over La Plata, this tornado was a F4 (winds up to 260 miles per hour or 116 m per second) and likely the most powerful to ever strike the state of Maryland. Here, the tornado is highlighted by the Sun, which is low in the western sky. Whitecaps were whipped up by the twister as it passed over the bay.

The lower photo, taken by Eric Beach, shows some of the remarkable baseball-sized hail stones that pummeled the community of Pomfrey, Maryland, a few miles from La Plata. Note the protuberances on the stones. This is evidence that they were subjected to a series of strong updrafts, which enabled them to increase in size each time they passed through layers of supercooled water droplets. Eventually, they were too large to be supported by the storm's vertical motions. Hail greater than 3/4 inch (1.9 cm) in diameter is a criterion for a severe thunderstorm.