A southerly flow between upper-level low pressure over the Midwest and upper-level high pressure over the Atlantic Ocean produced a warm and moist airmass over the region. A surface trough also remained overhead during this time. The instability from the airmass along with the surface trough triggered showers and thunderstorms. High amounts of instability along with strong winds aloft caused thunderstorms to become severe with large hail being the primary threat.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 14:57:00 to 26-MAY-11 14:57:00 (EST-5)
Location: MC COOLE
Magnitude: 1.00 
Reported by: Trained Spotter

Hail up to the size of quarters was reported near McCoole.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:02:00 to 26-MAY-11 15:02:00 (EST-5)
Location: DAWSON
Magnitude: 1.00 
Reported by: Trained Spotter

Quarter sized hail was reported near McCoole.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 16:03:00 to 26-MAY-11 16:03:00 (EST-5)
Location: BELLE GROVE
Magnitude: 2.00 
Property damage: 10.00K
Reported by: Public

Hail up to two inches in diameter was reported near Bellegrove. The large hail was responsible for four broken windows along with damage to vehicles.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 16:03:00 to 26-MAY-11 16:03:00 (EST-5)
Location: BELLE GROVE
Magnitude: 1.75 
Reported by: Public

Hail up to the size of golf balls was reported near Bellegrove.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 16:01:00 to 26-MAY-11 16:01:00 (EST-5)
Location: PINEY GROVE
Magnitude: 1.50 
Reported by: Public

Hail up to the size of ping pong balls was reported about three miles west of Bellegrove.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 16:02:00 to 26-MAY-11 16:02:00 (EST-5)
Location: BELLE GROVE
Magnitude: 1.75 
Reported by: Public

Hail up to the size of golf balls was reported near Bellegrove.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 16:02:00 to 26-MAY-11 16:02:00 (EST-5)
Location: BELLE GROVE
Magnitude: 1.75 
Reported by: Public

Hail up to the size of golf balls was reported near Bellegrove.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 16:04:00 to 26-MAY-11 16:04:00 (EST-5)
Location: BELLE GROVE
Magnitude: 2.00 
Reported by: Public

Hail up to two inches in diameter was reported near Bellegrove.

Hail in WASHINGTON, MARYLAND
From 26-MAY-11 16:15:00 to 26-MAY-11 16:15:00 (EST-5)
Location: HANCOCK
Magnitude: 1.75 
Reported by: Unknown

Golf ball sized hail was reported in Hancock.

Hail in WASHINGTON, MARYLAND
From 26-MAY-11 16:25:00 to 26-MAY-11 16:25:00 (EST-5)
Location: INDIAN SPGS
Magnitude: 1.00 
Reported by: Public

Quarter sized hail was reported near Pecktonville.

Hail in WASHINGTON, MARYLAND
From 26-MAY-11 16:25:00 to 26-MAY-11 16:25:00 (EST-5)
Location: INDIAN SPGS
Magnitude: 1.00 
Reported by: Public

Quarter sized hail was reported near Pecktonville.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 16:33:00 to 26-MAY-11 16:33:00 (EST-5)
Location: OLDTOWN
Magnitude: 1.75 
Reported by: Trained Spotter

Golf ball sized hail was reported near Oldtown.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:33:00 to 26-MAY-11 15:33:00 (EST-5)
Location: PINTO
Magnitude: 1.00 
Reported by: Public

Quarter sized hail was reported near Pinto.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:32:00 to 26-MAY-11 15:32:00 (EST-5)
Location: SPRING GAP
Magnitude: 1.00 
Reported by: Trained Spotter

Quarter sized hail was estimated at Spring Gap.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:19:00 to 26-MAY-11 15:19:00 (EST-5)
Location: EVITTS CREEK
Magnitude: 1.25 
Reported by: Public

Half dollar sized hail was reported near Cumberland.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:20:00 to 26-MAY-11 15:20:00 (EST-5)
Location: CUMBERLAND
Magnitude: 1.25 
Reported by: Public

Half dollar sized hail was reported near Cumberland.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:50:00 to 26-MAY-11 15:50:00 (EST-5)
Location: FLINTSTONE
Magnitude: 1.25 
Reported by: Public

Half dollar sized hail was reported near Flintstone.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:50:00 to 26-MAY-11 15:50:00 (EST-5)
Location: FLINTSTONE
Magnitude: 1.00 
Reported by: Public

Quarter sized hail was reported near Flintstone.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:42:00 to 26-MAY-11 15:42:00 (EST-5)
Location: RIDGELEY
Magnitude: 1.00 
Reported by: Public

Quarter sized hail was reported near Pumpkin Center.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:55:00 to 26-MAY-11 15:55:00 (EST-5)
Location: LITTLE ORLEANS
Magnitude: 2.75 
Reported by: Public

Baseball sized hail was reported near Little Orleans.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:58:00 to 26-MAY-11 15:58:00 (EST-5)
Location: PINEY GROVE
Magnitude: 2.50 
Property damage: 2.00K
Reported by: Public

Tennis ball sized hail covered a patio and produced minor roof damage near Bellegrove.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:57:00 to 26-MAY-11 15:57:00 (EST-5)
Location: PINEY GROVE
Magnitude: 2.25 
Property damage: 5.00K
Reported by: Public

Hail up to 2.25 inches in diameter was reported near Bellegrove. Hail caused minor roof damage along with broken windows.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:58:00 to 26-MAY-11 15:58:00 (EST-5)
Location: PINEY GROVE
Magnitude: 2.00 
Reported by: Public

Hail up to 2.00 inches in diameter was reported near Bellegrove.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 16:00:00 to 26-MAY-11 16:00:00 (EST-5)
Location: PINEY GROVE
Magnitude: 2.00 
Property damage: 5.00K
Reported by: Public

Hail up to 2.00 inches in diameter was reported near Little Orleans. Hail caused dents in vehicles.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:57:00 to 26-MAY-11 15:57:00 (EST-5)
Location: LITTLE ORLEANS
Magnitude: 2.25 
Reported by: Public

Hail up to 2.25 inches in diameter was reported near Little Orleans.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:55:00 to 26-MAY-11 15:55:00 (EST-5)
Location: PINEY GROVE
Magnitude: 1.00 
Reported by: Public

Quarter sized hail was reported near Little Orleans.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:59:00 to 26-MAY-11 15:59:00 (EST-5)
Location: BELLE GROVE
Magnitude: 1.25 
Reported by: Public

Half dollar sized hail was reported near Bellegrove.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:58:00 to 26-MAY-11 15:58:00 (EST-5)
Location: PINEY GROVE
Magnitude: 1.25 
Reported by: Public

Half dollar sized hail was reported near Bellegrove.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:58:00 to 26-MAY-11 15:58:00 (EST-5)
Location: PINEY GROVE
Magnitude: 1.25 
Reported by: Public

Half dollar sized hail was reported near Bellegrove.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 16:03:00 to 26-MAY-11 16:03:00 (EST-5)
Location: RIDGELEY
Magnitude: 1.75 
Reported by: Public

Golf ball sized hail was reported near North Branch.

Thunderstorm Wind in ALLEGANY, MARYLAND
From 26-MAY-11 16:03:00 to 26-MAY-11 16:03:00 (EST-5)
Location: BELLE GROVE
Magnitude: 52.00 EG
Property damage: 1.00K
Reported by: Public

A tree six inches in diameter was down due to thunderstorm winds.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:30:00 to 26-MAY-11 15:30:00 (EST-5)
Location: SPRING GAP
Magnitude: 1.25 
Reported by: Trained Spotter

Hail up to the size of half dollars was reported at Spring Gap.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 16:02:00 to 26-MAY-11 16:02:00 (EST-5)
Location: PINEY GROVE
Magnitude: 2.00 
Property damage: 10.00K
Reported by: Public

Hail up to two inches in diameter was reported near Bellegrove. Hail caused dents in cars.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:00:00 to 26-MAY-11 15:00:00 (EST-5)
Location: MC COOLE
Magnitude: 1.50 
Reported by: Trained Spotter

Hail up to the size of ping pong balls was reported just north of Keyser.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:55:00 to 26-MAY-11 15:55:00 (EST-5)
Location: LITTLE ORLEANS
Magnitude: 1.75 
Reported by: Public

Golf ball sized hail was reported near Flintstone.

Hail in WASHINGTON, MARYLAND
From 26-MAY-11 16:05:00 to 26-MAY-11 16:05:00 (EST-5)
Location: FOREST PARK
Magnitude: 2.75 
Reported by: Fire Department/Rescue

Hail up to the size of baseballs was reported near Forest Park.

Hail in ALLEGANY, MARYLAND
From 26-MAY-11 15:35:00 to 26-MAY-11 15:35:00 (EST-5)
Location: LUKE
Magnitude: 1.00 
Reported by: Public

Quarter sized hail was reported at Westernport.

Thunderstorm Wind in ALLEGANY, MARYLAND
From 26-MAY-11 15:33:00 to 26-MAY-11 15:33:00 (EST-5)
Location: OLDTOWN
Magnitude: 56.00 EG
Property damage: 3.00K
Reported by: County Official

Multiple trees were down in Oldtown.