Thursday's second round of snow, sleet and rain was so intense it spawned reports around the region of thundersnow, that bizarre winter weather phenomenon that acquainted itself with many around Baltimore in a snowy winter four years ago.
Two or three cloud-to-ground lightning strikes were reported in Anne Arundel County between about 5 p.m. and 7 p.m. Thursday, said Eric Wanenchak, a meteorologist with AccuWeather.com. A mix of sleet and snow was falling at that time, an indication that there was some warm air overhead mixing in with the cold.
Thundersnow occurs much like thunder does in a summer storm -- strong vertical motion of heat and moisture within tall storm clouds that creates an electrical difference between two clouds or between a cloud and the ground. But that phenomenon is uncommon in weather cold enough to produce snow.
"It's relatively rare, especially for this part of the country," Wanenchak said. "It usually tends to happen up toward New England ... but it can happen just about anywhere up and down the East Coast."