A stalled frontal boundary acted as the triggering point for an initial line of showers and thunderstorms, with many of the storms becoming severe with strong moisture advection combining with diurnal heating and leading to an unstable air mass. The remnants of Tropical System Bill moved through the Mid-Atlantic overnight, continuing the severe threat late into the early part of the overnight hours. As winds backed with the tropical system, increasing directional and magnitude shear led to the development of tornadoes.

Thunderstorm Wind in ANNE ARUNDEL, MARYLAND
From 20-JUN-15 20:50:00 to 20-JUN-15 20:50:00 (EST-5)
Location: LEITCH
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: Broadcast Media

A tree was reported down near the intersection of Franklin Gibson Rd and Leitch Rd. Reported by WBAL-TV Baltimore.

Thunderstorm Wind in ANNE ARUNDEL, MARYLAND
From 20-JUN-15 15:15:00 to 20-JUN-15 15:15:00 (EST-5)
Location: BESTGATE
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down on Harbarts Court at Sigfriend Court.

Thunderstorm Wind in BALTIMORE, MARYLAND
From 20-JUN-15 20:03:00 to 20-JUN-15 20:03:00 (EST-5)
Location: SPARROWS PT
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down near the 900 block of Cathedral St.

Thunderstorm Wind in HOWARD, MARYLAND
From 20-JUN-15 19:48:00 to 20-JUN-15 19:48:00 (EST-5)
Location: ELKRIDGE
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down near the 5500 block of Race Rd.

Thunderstorm Wind in ST. MARY'S, MARYLAND
From 20-JUN-15 21:10:00 to 20-JUN-15 21:10:00 (EST-5)
Location: BEACHVILLE
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down across Beachville Rd.

Thunderstorm Wind in BALTIMORE, MARYLAND
From 20-JUN-15 19:54:00 to 20-JUN-15 19:54:00 (EST-5)
Location: HALETHORPE
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down on Valley Rd between Wilkens Ave and Hilltop Ave.

Thunderstorm Wind in FREDERICK, MARYLAND
From 20-JUN-15 18:46:00 to 20-JUN-15 18:46:00 (EST-5)
Location: BUCKEYSTOWN
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported near the intersection of New Design Rd and Manor Woods Rd.

Thunderstorm Wind in BALTIMORE, MARYLAND
From 20-JUN-15 19:59:00 to 20-JUN-15 19:59:00 (EST-5)
Location: HALETHORPE
Magnitude: 50.00 MG
Reported by: Mesonet

Measured at Umbc1.

Thunderstorm Wind in CALVERT, MARYLAND
From 20-JUN-15 20:33:00 to 20-JUN-15 20:33:00 (EST-5)
Location: DARES BEACH
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down near the intersection of North Cassell Blvd and Wilson Rd.

Thunderstorm Wind in HOWARD, MARYLAND
From 20-JUN-15 20:05:00 to 20-JUN-15 20:05:00 (EST-5)
Location: DORSEY
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree about 10 ft tall was reported down.

Thunderstorm Wind in FREDERICK, MARYLAND
From 20-JUN-15 18:46:00 to 20-JUN-15 18:46:00 (EST-5)
Location: FEAGAVILLE
Magnitude: 52.00 EG
Property damage: 1.00K
Crop damage: 1.00K
Reported by: Trained Spotter

A 5 inch diameter tree was knocked down and several dozen 3-inch branches were scattered around the ground. Half of the spotters corn crop was destroyed. Reported by FK042.

Thunderstorm Wind in WASHINGTON, MARYLAND
From 20-JUN-15 18:44:00 to 20-JUN-15 18:44:00 (EST-5)
Location: CHEWSVILLE
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: Trained Spotter

A tree was reported down on Route 62 near Old Forge Rd.

Thunderstorm Wind in CHARLES, MARYLAND
From 20-JUN-15 19:38:00 to 20-JUN-15 19:38:00 (EST-5)
Location: RISON
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: Trained Spotter

Several branches about 3 inches in diameter were reported scattered around the ground.

Thunderstorm Wind in CALVERT, MARYLAND
From 20-JUN-15 20:32:00 to 20-JUN-15 20:32:00 (EST-5)
Location: STOAKLEY
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down near the intersection of Plum Point Rd and Solomons Island Rd.

Thunderstorm Wind in FREDERICK, MARYLAND
From 20-JUN-15 18:44:00 to 20-JUN-15 18:44:00 (EST-5)
Location: POINTS OF ROCKS
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down near the 1700 block of Ballender Creek Pike.

Thunderstorm Wind in FREDERICK, MARYLAND
From 20-JUN-15 18:54:00 to 20-JUN-15 18:54:00 (EST-5)
Location: FEAGAVILLE
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down near the intersection of Ballenger Creek Pike and South Renn Rd.

Thunderstorm Wind in CHARLES, MARYLAND
From 20-JUN-15 20:17:00 to 20-JUN-15 20:17:00 (EST-5)
Location: LOVES
Magnitude: 52.00 EG
Reported by: Trained Spotter

Numerous small trees were downed and damaged. Reported by CH068.

Thunderstorm Wind in ST. MARY'S, MARYLAND
From 20-JUN-15 20:15:00 to 20-JUN-15 20:15:00 (EST-5)
Location: THOMPSON CORNER
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down on Thompson Corner Rd.

Tornado in FREDERICK, MARYLAND
From 20-JUN-15 18:39:00 to 20-JUN-15 18:45:00 (EST-5)
Location: TUSCARORA
Tornado F-scale: EF0
Property damage: 5.00K
Reported by: NWS Storm Survey

A team from the National Weather Service in Sterling, VA conducted a ground survey of tornado damage along a 1.5 mile path beginning near the intersection of Tuscarora Road and Buckeystown Pike, then moved northeast to Greenfield Road. Based on this
survey along with radar data, the team determined an EF-0 tornado occurred along this path.
The tornado was approximately 75 yards wide with maximum winds of 65 mph. Large tree branches were snapped half way up and trees were nearly pushed over from south to north near the intersection of Tuscarora Road and Buckeystown pike. Additional tree damage occurred at two residences just north of the intersection. Another small tree was snapped over in a southeast to northwest direction
about one half mile north of the residences. A large tree was snapped over at the base in a north to south direction at a residence just off Buckeystown Pike near Greenfield Road. On the backside of the residence and along Greenfield Road, an
additional large tree branch was also snapped in a north to south direction. No additional damage was noted to the north of Greenfield Road.

Thunderstorm Wind in ST. MARY'S, MARYLAND
From 20-JUN-15 20:09:00 to 20-JUN-15 20:09:00 (EST-5)
Location: BUDDS CREEK
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

Numerous trees were reported down around Country Lakes.

Thunderstorm Wind in HARFORD, MARYLAND
From 20-JUN-15 20:46:00 to 20-JUN-15 20:46:00 (EST-5)
Location: GIBSON MANOR
Magnitude: 52.00 EG
Property damage: 2.00K
Reported by: 911 Call Center

A 5 foot in diameter tree was reported down on multiple power lines on Thomas Run Rd near Kalmia Rd.

Thunderstorm Wind in HARFORD, MARYLAND
From 20-JUN-15 20:41:00 to 20-JUN-15 20:41:00 (EST-5)
Location: GIBSON
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down at the intersection of Prospect Mill Rd and Route 543.

Thunderstorm Wind in HARFORD, MARYLAND
From 20-JUN-15 20:42:00 to 20-JUN-15 20:42:00 (EST-5)
Location: FOUNTAIN GREEN
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down at the intersection of Thomas Run Rd and Route 543.

Thunderstorm Wind in HARFORD, MARYLAND
From 20-JUN-15 20:25:00 to 20-JUN-15 20:25:00 (EST-5)
Location: JOPPA
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: Broadcast Media

A tree was reported down on I-95. Reported by WBAL-TV Baltimore.

Thunderstorm Wind in HOWARD, MARYLAND
From 20-JUN-15 19:45:00 to 20-JUN-15 19:45:00 (EST-5)
Location: JONESTOWN
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down on Old Montgomery Rd near Brightfield Rd.

Thunderstorm Wind in HOWARD, MARYLAND
From 20-JUN-15 19:45:00 to 20-JUN-15 19:45:00 (EST-5)
Location: DORSEY
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down on Meadow Ridge Rd near Huntshire Dr.

Thunderstorm Wind in HOWARD, MARYLAND
From 20-JUN-15 19:38:00 to 20-JUN-15 19:38:00 (EST-5)
Location: EAST LIOAK
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down on Rivendell Lane near Harpers Farm Rd.

Thunderstorm Wind in BALTIMORE, MARYLAND
From 20-JUN-15 20:05:00 to 20-JUN-15 20:05:00 (EST-5)
Location: SPARROWS PT
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down along Harford Rd.

Thunderstorm Wind in BALTIMORE, MARYLAND
From 20-JUN-15 19:59:00 to 20-JUN-15 19:59:00 (EST-5)
Location: WOODLAWN
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Numerous tree tops were snapped and tree limbs were reported across the ground near the interchange of I-695 and Security Blvd.

Thunderstorm Wind in HOWARD, MARYLAND
From 20-JUN-15 19:38:00 to 20-JUN-15 19:38:00 (EST-5)
Location: DAYTON
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: 911 Call Center

A tree was reported down at the intersection of Ten Oaks Rd and Smallwood Court.

Thunderstorm Wind in HARFORD, MARYLAND
From 20-JUN-15 20:54:00 to 20-JUN-15 20:54:00 (EST-5)
Location: STREET
Magnitude: 52.00 EG
Property damage: 2.00K
Reported by: Public

Portions of the roof on a shed and barn were blown off. A hay wagon was completely destroyed.