A cold front passed through the area on the 27th. Ahead of the boundary, a southerly flow led to plenty of moisture an unstable atmosphere. A potent upper-level low caused stronger winds aloft as well. Some thunderstorms associated with the cold front became severe due to the instability and stronger winds aloft.

Thunderstorm Wind in MONTGOMERY, MARYLAND
From 27-JUL-18 14:40:00 to 27-JUL-18 14:40:00 (EST-5)
Location: TRAVILAH
Magnitude: 50.00 EG
Reported by: Law Enforcement

A tree was down on power lines in the 13100 Block of Travilah Road.

Thunderstorm Wind in HOWARD, MARYLAND
From 27-JUL-18 15:20:00 to 27-JUL-18 15:20:00 (EST-5)
Location: KNOLLWOOD
Magnitude: 50.00 EG
Reported by: Department of Highways

A tree was down on MD 97 south of Roxbury Mill Road.

Thunderstorm Wind in FREDERICK, MARYLAND
From 27-JUL-18 15:46:00 to 27-JUL-18 15:46:00 (EST-5)
Location: PETERSVILLE
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was down in the roadway near the intersection of Petersville Road and Jefferson Pike.

Thunderstorm Wind in BALTIMORE, MARYLAND
From 27-JUL-18 15:52:00 to 27-JUL-18 15:52:00 (EST-5)
Location: HOLBROOK
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was down at Liberty Road and Wards Chapel Road.

Thunderstorm Wind in FREDERICK, MARYLAND
From 27-JUL-18 15:57:00 to 27-JUL-18 15:57:00 (EST-5)
Location: POINTS OF ROCKS
Magnitude: 50.00 EG
Reported by: Law Enforcement

A tree was down in the roadway on MD-464 just west of US-15.

Thunderstorm Wind in FREDERICK, MARYLAND
From 27-JUL-18 16:02:00 to 27-JUL-18 16:02:00 (EST-5)
Location: DOUBS
Magnitude: 50.00 EG
Reported by: Law Enforcement

A large tree was down blocking US-15 near Basford Road.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 17:04:00 to 27-JUL-18 17:04:00 (EST-5)
Location: ABINGDON
Magnitude: 50.00 EG
Reported by: Emergency Manager

A tree was down in the 1000 Block of Hookers Mill Road.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 17:04:00 to 27-JUL-18 17:04:00 (EST-5)
Location: GLENWOOD
Magnitude: 50.00 EG
Reported by: Emergency Manager

A tree was down near the intersection of Westwood Drive and Bonnie Avenue.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 17:07:00 to 27-JUL-18 17:07:00 (EST-5)
Location: CALVARY
Magnitude: 50.00 EG
Reported by: Emergency Manager

A tree was down blocking the roadway in the 1700 Block of South Fountain Green Road.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 17:08:00 to 27-JUL-18 17:08:00 (EST-5)
Location: CALVARY
Magnitude: 50.00 EG
Reported by: Emergency Manager

Wires were down near the intersection of MD-136 Calvary Road and Graftons Lane as well as the 400 block of Calvary Road.

Thunderstorm Wind in FREDERICK, MARYLAND
From 27-JUL-18 16:06:00 to 27-JUL-18 16:06:00 (EST-5)
Location: FREDERICK ARPT
Magnitude: 50.00 EG
Reported by: Law Enforcement

Wires were down near the intersection of East Patrick Street and Hamilton Avenue.

Thunderstorm Wind in FREDERICK, MARYLAND
From 27-JUL-18 16:10:00 to 27-JUL-18 16:10:00 (EST-5)
Location: URBANA
Magnitude: 50.00 EG
Reported by: Law Enforcement

Wires were down near the intersection of Peters Road and Thurston Road.

Thunderstorm Wind in FREDERICK, MARYLAND
From 27-JUL-18 16:10:00 to 27-JUL-18 16:10:00 (EST-5)
Location: REELS MILL
Magnitude: 50.00 EG
Reported by: Broadcast Media

A tree was down blocking MD-355 near Ball Road.

Thunderstorm Wind in ANNE ARUNDEL, MARYLAND
From 27-JUL-18 16:23:00 to 27-JUL-18 16:23:00 (EST-5)
Location: FERNDALE
Magnitude: 50.00 EG
Reported by: 911 Call Center

Multiple trees were down in the Linthicum.

Thunderstorm Wind in FREDERICK, MARYLAND
From 27-JUL-18 16:23:00 to 27-JUL-18 16:23:00 (EST-5)
Location: NEW MARKET
Magnitude: 50.00 EG
Reported by: Law Enforcement

A tree fell on power lines along Boyers Mill Road between Fin Drive and New Market Court.

Thunderstorm Wind in BALTIMORE, MARYLAND
From 27-JUL-18 16:29:00 to 27-JUL-18 16:29:00 (EST-5)
Location: LUTHERVILLE
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was down along the 200 Block of Welford Road.

Thunderstorm Wind in MONTGOMERY, MARYLAND
From 27-JUL-18 16:30:00 to 27-JUL-18 16:30:00 (EST-5)
Location: CEDAR GROVE
Magnitude: 50.00 EG
Reported by: Law Enforcement

A tree was down on wires along the 23900 Block of Stringtown Road.

Thunderstorm Wind in FREDERICK, MARYLAND
From 27-JUL-18 16:34:00 to 27-JUL-18 16:34:00 (EST-5)
Location: UNIONVILLE
Magnitude: 50.00 EG
Reported by: Law Enforcement

Wires were down along the 8700 Block of Mapleville Road.

Thunderstorm Wind in BALTIMORE, MARYLAND
From 27-JUL-18 16:47:00 to 27-JUL-18 16:47:00 (EST-5)
Location: FORK
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was down at Glen Arm Road and Hartford Road.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 16:57:00 to 27-JUL-18 16:57:00 (EST-5)
Location: SINGER
Magnitude: 50.00 EG
Reported by: Emergency Manager

A tree was down near the intersection of Singer Road and Winters Run Road.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 16:58:00 to 27-JUL-18 16:58:00 (EST-5)
Location: BYNUM
Magnitude: 50.00 EG
Reported by: Emergency Manager

A tree was down near the intersection of Grafton Shop Road and Osborne Parkway.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 17:00:00 to 27-JUL-18 17:00:00 (EST-5)
Location: ABINGDON
Magnitude: 50.00 EG
Reported by: Emergency Manager

A tree was down near the intersection of Federal Lane and Abingdon Road.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 17:00:00 to 27-JUL-18 17:00:00 (EST-5)
Location: EMMORTON
Magnitude: 50.00 EG
Reported by: Emergency Manager

A tree was down near the intersection of East Wheel Road and Cedar Lane.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 17:00:00 to 27-JUL-18 17:00:00 (EST-5)
Location: BEL AIR
Magnitude: 52.00 EG
Reported by: Emergency Manager

A tree limb was down blocking the roadway near the intersection of North Tollgate Road and Boulton Street. Large trees were also across the roadway near the intersection of Barnes Street and Powell Avenue. A tree was down across both lanes of Stafford Road near Susuquehanna Stage Park. Two trees were down on James Run Road near the intersection with Tower Road. A tree was down on Wesleyan Drive near the intersection of State Route 136.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 17:01:00 to 27-JUL-18 17:01:00 (EST-5)
Location: BELCAMP
Magnitude: 50.00 EG
Reported by: Emergency Manager

A tree and wires were down near the intersection of Forest Green Road and Park Beach Drive.

Thunderstorm Wind in BALTIMORE, MARYLAND
From 27-JUL-18 20:37:00 to 27-JUL-18 20:37:00 (EST-5)
Location: OVERLEA
Magnitude: 50.00 EG
Reported by: Broadcast Media

Numerous trees were down on Rosemont Avenue.

Thunderstorm Wind in CHARLES, MARYLAND
From 27-JUL-18 14:23:00 to 27-JUL-18 14:23:00 (EST-5)
Location: MORGANTOWN
Magnitude: 50.00 EG
Reported by: 911 Call Center

A large tree was down at the intersection of Morgantown Road and Waverly Point Road.

Thunderstorm Wind in CHARLES, MARYLAND
From 27-JUL-18 14:24:00 to 27-JUL-18 14:24:00 (EST-5)
Location: LA PLATA
Magnitude: 50.00 EG
Reported by: 911 Call Center

A large tree was down across Tip Hill Court.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 16:50:00 to 27-JUL-18 16:50:00 (EST-5)
Location: FALLSTON ARPT
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was down on the 2700 Block of Laurel Brook Road.

Hail in BALTIMORE CITY (C), MARYLAND
From 27-JUL-18 16:30:00 to 27-JUL-18 16:30:00 (EST-5)
Location: CAMDEN
Magnitude: 1.25 
Reported by: Public

Half dollar sized hail was reported at Oriole Park.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 17:01:00 to 27-JUL-18 17:01:00 (EST-5)
Location: SEWELL
Magnitude: 50.00 EG
Reported by: Emergency Manager

A tree was down near the intersection of Belcamp Road and Sanford Court.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 17:04:00 to 27-JUL-18 17:04:00 (EST-5)
Location: STEPNEY
Magnitude: 50.00 EG
Reported by: Emergency Manager

A tree was down near the intersection of MD-159 Perryman Road and Cranberry Road.

Thunderstorm Wind in CALVERT, MARYLAND
From 27-JUL-18 14:20:00 to 27-JUL-18 14:20:00 (EST-5)
Location: COVE PT
Magnitude: 50.00 EG
Reported by: Fire Department/Rescue

Multiple trees were down on the Pioneer Trail. Numerous trees were uprooted near Cove Point as well.

Thunderstorm Wind in HARFORD, MARYLAND
From 27-JUL-18 17:01:00 to 27-JUL-18 17:01:00 (EST-5)
Location: EMMORTON
Magnitude: 50.00 EG
Reported by: Emergency Manager

A tree was down near the intersection of Laurel Bush Road and Temple Drive.