The National Weather Service said it will investigate whether severe damage in the Manassas area during a Wednesday night thunderstorm was caused by a tornado or straight line winds.
The violent thunderstorm knocked a tree into a house in Manassas and left thousands without power in Fairfax and Prince William.
The tree struck the house in the area of Old Dominion Drive and Sheridan Lane near the Prince William Fairgrounds around 11:30 p.m., but the resident there was able to escape unharmed, according to the Manassas Volunteer Fire Company. Other residents reported trees and limbs down in the same area.
The weather service defines straight line winds as the downdraft of a fast-moving thunderstorm. In Wednesday night’s storm, the system was capable of producing winds in excess of 60 mph.
The storm knocked out power to about 12,000 Dominion Virginia Power customers in Fairfax County and about 1,150 more in Prince William County. About 700 Northern Virginia Electric Cooperative customers lost power during the storm.
The weather service says more severe storms are possible Thursday, especially in the afternoon and evening.