High pressure over the western Atlantic continued to usher in hot and humid air with a southwest flow. An upper-level disturbance in the zonal flow triggered showers and thunderstorms across portions of Maryland.
Every event with a place to put it. Tap one for its entry below.
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.
High pressure over the western Atlantic continued to usher in hot and humid air with a southwest flow. An upper-level disturbance in the zonal flow triggered showers and thunderstorms across portions of Maryland. Moderate amounts of instability due to the hot and humid air mass caused some thunderstorms to produce damaging winds.
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 18, 7:31 PM EST, 2 hours 47 minutes earlier.
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</html>The Sterling radar (KLWX), 23 km away, was scanning. The volume nearest the first event began at 03:18 UTC.
10 thunderstorm wind. Local standard time, as filed.
A large tree was down along Glen Road.
A tree was down along West Central Avenue.
A tree was down at College Parkway and Shore Acres Road.
Trees were down around Ellicott City.
A wind gust of 62 mph was measured at the Baltimore-Washington International Airport.
A wind gust of 72 mph was measured at the Baltimore-Washington International Airport.
A wind gust of 58 mph was measured at Glen Burnie.
A tree that was two feet in diameter was snapped.
Large limbs were down from Bowleys Quarters to Middle River.
A wind gust was estimated around 60 mph at White Marsh.
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: 248267, 248289, 248290, 248268, 248269, 248270, 248271, 248272, 248273, 248274.