Low pressure moved east toward the Chesapeake Bay during the early morning, encountering a very moist low-level atmosphere. Lift was sufficient to produce thunderstorms, a series of which trained across southern Harford county for several hours, producing 2-4 inches of rain and a report of flash flooding.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS LWX wrote it up.
Low pressure moved east toward the Chesapeake Bay during the early morning, encountering a very moist low-level atmosphere. Lift was sufficient to produce thunderstorms, a series of which trained across southern Harford county for several hours, producing 2-4 inches of rain and a report of flash flooding.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Baltimore/Washington wrote its last area forecast discussion before the first event at Jul 9, 5:09 PM EST, 13 hours 41 minutes earlier.
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</html>The Dover AFB radar (KDOX), 99 km away, was scanning. The volume nearest the first event began at 11:50 UTC.
1 flash flood. Local standard time, as filed.
Edgewood Road at the CSX Railroad Overpass was flooded and closed. A spotter near the event reported 3.75 inches of rain in 2.5 hours.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Maryland in 2010Every state in 2010This day in weather historyWarnings in Maryland, July 2010
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 248577.