A warm frontal boundary returned northward into southeastern Oklahoma by the afternoon hours of August 22nd ahead of a strong upper level disturbance that translated southeastward into the Southern Plains. Warm and moist air returned northward into eastern Oklahoma ahead of this disturbance. By late afternoon, the atmosphere had become moderately unstable and thunderstorms initiated north of the warm front over north central Oklahoma. These storms moved east and southeast into northeastern Oklahoma during the early evening resulting in large hail and damaging wind gusts. Additional storms developed closer to the warm front later in the evening. Plenty of wind shear existed in the low and mid levels of the atmosphere and combined with the instability, the environment supported the development of several supercell thunderstorms. These storms affected Okfuskee, McIntosh, Pittsburg, and Okmulgee Counties with hail up to softball size and widespread damage from wind-driven hail. These storms later evolved into a squall line, which produced damaging wind gusts across portions of southeastern Oklahoma.

Hail in OKFUSKEE, OKLAHOMA
From 22-OCT-11 17:07:00 to 22-OCT-11 17:29:00 (CST-6)
Location: PADEN
Magnitude: 4.00 
Property damage: 75.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A supercell thunderstorm produced a broad swath of damage that was the result of wind-driven hail up to about four inches in diameter. The wind-driven hail destroyed the roofs and sides of homes, broke many windows from homes and automobilies, and stripped trees of leaves and even bark in some cases. Witnesses indicated that the hail lasted for about 20 minutes in some locations and several inches of hail was still piled up against homes the next morning before it completely melted.

Hail in OKFUSKEE, OKLAHOMA
From 22-OCT-11 17:30:00 to 22-OCT-11 17:45:00 (CST-6)
Location: PADEN
Magnitude: 4.00 
Property damage: 50.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A second supercell thunderstorm produced a broad swath of damage as a result of wind-driven hail up to about four inches in diameter. The wind-driven hail destroyed the roofs and sides of homes, broke out windows from homes and automobiles, and stripped trees of leaves and even the bark in some cases. Witnesses indicated that the hail lasted for about 20 minutes in some locations and several inches of hail was still piled up against homes the next morning before it completely melted.

Hail in OKFUSKEE, OKLAHOMA
From 22-OCT-11 17:50:00 to 22-OCT-11 18:20:00 (CST-6)
Location: BEARDEN
Magnitude: 4.00 
Property damage: 100.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

The second and southernmost supercell continued to move slowly east-southeast leaving a broad swath of damage in its wake as a result of wind-driven hail up to about four inches in diameter. The wind-driven hail destroyed the roofs and siding of homes, broke windows out of homes and automobilies, and stripped trees of leaves and even bark in some cases. Witnesses indicated that the hail lasted for about 20 minutes in some places and several inches of hail was still piled up against homes the next morning before it completely melted.

Thunderstorm Wind in OKFUSKEE, OKLAHOMA
From 22-OCT-11 18:10:00 to 22-OCT-11 18:10:00 (CST-6)
Location: OKEMAH
Magnitude: 65.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Emergency management reported trees and power lines blown down by strong thunderstorm wind in and south of town. Minor structural damage was also done to mobile homes.

Hail in TULSA, OKLAHOMA
From 22-OCT-11 18:13:00 to 22-OCT-11 18:13:00 (CST-6)
Location: OWASSO
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in ROGERS, OKLAHOMA
From 22-OCT-11 18:29:00 to 22-OCT-11 18:29:00 (CST-6)
Location: CATOOSA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in OKMULGEE, OKLAHOMA
From 22-OCT-11 18:45:00 to 22-OCT-11 18:45:00 (CST-6)
Location: HECTOR
Magnitude: 60.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

The Oklahoma Mesonet station west of Hectorville measured 69 mph thunderstorm wind gusts.

Thunderstorm Wind in PITTSBURG, OKLAHOMA
From 22-OCT-11 20:13:00 to 22-OCT-11 20:13:00 (CST-6)
Location: SCIPIO
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Strong thunderstorm wind blew down large tree limbs.

Thunderstorm Wind in CHOCTAW, OKLAHOMA
From 22-OCT-11 22:10:00 to 22-OCT-11 22:10:00 (CST-6)
Location: HUGO
Magnitude: 58.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

The Oklahoma Mesonet station near Hugo measured 67 mph thunderstorm wind gusts.

Thunderstorm Wind in OKMULGEE, OKLAHOMA
From 22-OCT-11 17:45:00 to 22-OCT-11 17:45:00 (CST-6)
Location: BEGGS
Magnitude: 61.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Strong thunderstorm wind blew the roof off of a barn and blew down several trees and power lines.

Hail in OKFUSKEE, OKLAHOMA
From 22-OCT-11 18:34:00 to 22-OCT-11 18:34:00 (CST-6)
Location: WELEETKA
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorm Wind in OKMULGEE, OKLAHOMA
From 22-OCT-11 18:40:00 to 22-OCT-11 18:40:00 (CST-6)
Location: HECTOR
Magnitude: 62.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

The Oklahoma Mesonet station located west of Hectorville measured 71 mph thunderstorm wind gusts.

Thunderstorm Wind in LE FLORE, OKLAHOMA
From 22-OCT-11 20:48:00 to 22-OCT-11 20:48:00 (CST-6)
Location: SHADY PT
Magnitude: 65.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Strong thunderstorm wind blew down a large tree.