Severe thunderstorms developed along and ahead of a dry line across central Oklahoma during the afternoon of May 9th. The storms moved across eastern Oklahoma during the evening hours. Prior to the storms moving into the area, the atmosphere ahead of the dry line in eastern Oklahoma had become very unstable. This instability, combined with very strong wind shear associated with a strong trough of low pressure that moved into the Southern Plains from the Southern Rockies, resulted in the development of supercell thunderstorms. One of these supercells produced multiple tornadoes as it tracked along and near an outflow boundary from morning thunderstorms, which had settled across southeastern Oklahoma by the afternoon. One of the tornadoes was long-lived and damaging. In addition to the tornadoes in southeastern Oklahoma, the severe thunderstorms produced hail up to golfball size and damaging wind gusts across other portions of eastern Oklahoma.

Hail in PITTSBURG, OKLAHOMA
From 09-MAY-16 17:34:00 to 09-MAY-16 17:34:00 (CST-6)
Location: HAILEYVILLE
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in LATIMER, OKLAHOMA
From 09-MAY-16 17:38:00 to 09-MAY-16 17:38:00 (CST-6)
Location: WILBURTON
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in PAWNEE, OKLAHOMA
From 09-MAY-16 17:46:00 to 09-MAY-16 17:46:00 (CST-6)
Location: PAWNEE
Magnitude: 1.75 
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm Wind in LE FLORE, OKLAHOMA
From 09-MAY-16 19:05:00 to 09-MAY-16 19:05:00 (CST-6)
Location: OAK LODGE
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Strong thunderstorm wind blew down large tree limbs between Spiro and Pocola.

Hail in OSAGE, OKLAHOMA
From 09-MAY-16 19:46:00 to 09-MAY-16 19:46:00 (CST-6)
Location: SHIDLER ARPT
Magnitude: 1.50 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Hail in OSAGE, OKLAHOMA
From 09-MAY-16 20:27:00 to 09-MAY-16 20:27:00 (CST-6)
Location: PAWHUSKA
Magnitude: 1.25 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Hail in OSAGE, OKLAHOMA
From 09-MAY-16 20:43:00 to 09-MAY-16 20:43:00 (CST-6)
Location: PAWHUSKA
Magnitude: 1.75 
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Hail in WASHINGTON, OKLAHOMA
From 09-MAY-16 21:02:00 to 09-MAY-16 21:02:00 (CST-6)
Location: BARTLESVILLE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Tornado in CHOCTAW, OKLAHOMA
From 09-MAY-16 18:02:00 to 09-MAY-16 18:10:00 (CST-6)
Location: GOODLAND
Tornado F-scale: EF1
Property damage: 250.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This tornado developed west of Hugo and moved eastward across town. Numerous homes and businesses were damaged, storage buildings were destroyed, trees were uprooted, signs were blown down, and power poles were snapped. Based on this damage, maximum estimated wind in the tornado was 95 to 105 mph.

Hail in NOWATA, OKLAHOMA
From 09-MAY-16 21:26:00 to 09-MAY-16 21:26:00 (CST-6)
Location: NOWATA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Tornado in CHOCTAW, OKLAHOMA
From 09-MAY-16 18:25:00 to 09-MAY-16 18:26:00 (CST-6)
Location: VIRGIL
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Storm chasers and storm spotters observed this tornado, which developed during the life cycle of the Hugo Lake tornado from the same supercell updraft. This tornado was observed to be to the south of the other tornado. The NWS damage survey team could find no damage in the area where this tornado was suspected to be, as it was either over Lake Hugo or in the marsh land on the east side of the lake. Both areas were inaccessible, and therefore, no damage was known to exist from which a damage rating could be determined.

Tornado in CHOCTAW, OKLAHOMA
From 09-MAY-16 17:27:00 to 09-MAY-16 17:42:00 (CST-6)
Location: BOSWELL AMMONS ARPT
Tornado F-scale: EF3
Property damage: 3.00M
Crop damage: 0.00K
Reported by: NWS Storm Survey

This is the second segment of a two segment tornado that began at 624 pm CDT in Bryan County, Oklahoma. The tornado strengthened and widened rapidly after developing southeast of Bennington.  It was about 2500 yards wide and was producing EF-2 damage to trees by the time it reached the Choctaw County border at around 627 pm CDT.
In Choctaw County, the tornado continued to widen as it moved northeast, producing a damage path of about 1.8 miles across, to the southwest of Boswell. The tornado made a turn to the east at the N4000 Road and maintained an eastward movement until dissipating before reaching the N4090 Road. The tornado destroyed at least three mobile homes. Two injuries occurred in one of the mobile homes, one of which was a critical injury. Numerous homes were damaged by this tornado, with the worst damage including major loss of the roof structure and collapse of a few exterior walls. Numerous outbuildings were also destroyed. A metal, high-voltage transmission tower/truss was destroyed, and numerous power poles were snapped. Many trees were snapped or uprooted in the path. Trees in several areas were reduced to shortened trunks with short stumps where large limbs previously existed. Based on this damage, maximum estimated wind in this segment of the tornado was 140 to 150 mph.

Tornado in CHOCTAW, OKLAHOMA
From 09-MAY-16 18:18:00 to 09-MAY-16 18:30:00 (CST-6)
Location: OLD MESSER
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Several storm chasers and storm spotters observed this tornado, which remained over Lake Hugo for much of its life cycle. The NWS ground survey team investigated accessible areas of land on both the west and east sides of the lake, and could find no damage. Therefore, the specific details regarding this tornado had to be estimated, and a damage rating could not be determined.