Damaging Winds and Lightning Strike in Virginia, June 26, 1997

A pre-frontal squall line moving into very unstable air produced several instances of straight-line wind damage, including some from in-storm downbursts and others along the gust front. The most intense damage occurred early in the event, in northeast Frederick Co. A strong downburst, containing estimated winds of 80 to 100 mph, produced a swath of damage approximately 1 mile wide and 4 miles long between Welltown and Stephenson. The heaviest structural damage occurred with the onset of the downburst at an industrial park located just north of the intersection of interstate 81, federal highway 11 and state route 37. Damage at the park included one steel-frame building (under construction) which collapsed, and minor damage to several other buildings. The downburst raced into nearby forested areas, where heavy damage was sustained (numerous trees were uprooted or snapped) and some utility poles were felled. Thereafter, four residential homes sustained roof damage, with two declared uninhabitable. One large barn collapsed, as did three large sheds. Two mobile homes shifted off their moorings. A total of 50 structures sustained minor to major damage, including siding, gutters, windows, and roofs. Additional tree damage, including one onto a car, occurred in nearby Stephenson before the downburst dissipated.Other tree damage was reported in Madison and Clarke Cos. In Madison Co, trees were down across state route 231 near Roswell. Several trees fell in northern Clarke Co along local route 611. In northern Fauquier Co, power outages were fairly widespread - a result of lightning striking several transformers. In Arlington Co, a fallen tree blocked the intersection of Glebe and Chain Bridge roads. A local wind sensor recorded a gust of 62 mph at Thomas Jefferson High School.The line weakened as it travelled east, but still produced widespread (though scattered) tree and wire damage. Dozens of large limbs were knocked down in central Loudoun Co,with Leesburg particularly hard hit. Two large (30 lb.) planters were blown off a residence's deck in Leesburg, and a work scaffold was blown down at an under construction building in Sterling. In northwest Fairfax Co, several trees and large limbs were downed at the intersection of Holly Knoll Road and state route 7 near Dranesville. At least two of the trees had to be cleared from the roadway. Virginia Power reported 6700 customers were without power during the height of the storm in the Leesburg area. For their entire northern Virginia district, an estimated 17,300 customers were powerless.