Flash Flood and Hail in Maryland, June 13, 1998

A vigorous upper-level disturbance acted upon increasingly warm and humid air near the surface to produce a squall line of strong to severe thunderstorms which traversed central and northeastern Maryland during the afternoon. Overall, damage was dominated by numerous downed trees, large limbs, and power lines, though there were scattered occurrences of large hail.Montgomery Co was hardest hit. Though no one area received major damage, nearly all communities in the eastern two-thirds of the county had some trees, large limbs, or wires down. A portion of Woodfield Road (state route 124) was closed north of Gaithersburg; dozens of trees and large limbs were down along the state route 28 corridor from Darnestown to Rockville. Farther south, fallen trees closed a portion of Persimmon Tree Road in Potomac. The most harrowing experience occurred in Glen Echo, where two vehicles were damaged by a large limb and falling wires. The two males were rescued; the woman was brought to a nearby hospital for observation. In all, county emergency management officials reported a dozen trees on houses and several others on vehicles across the county. The combination of wind and lightning knocked out power to over 40,000 Potomac Electric Power Co. customers in Montgomery and Prince George's Cos.Across northeastern Maryland, tree damage was confined to smaller limbs and some wires. However, a slower moving storm dropped at least 1 1/2 inches of rain across central and eastern Harford Co, creating a period of flash flooding which required at least one rescue of a stranded vehicle. Several reports of street flooding were received from both Aberdeen and Havre de Grace.Earlier, tree and wire damage was noted in southern Carroll and western Howard Cos, with the more substantial damage in Howard. Baltimore Gas and Electric reported at least 10,000 customers lost electricity in these areas at the peak of the storm.