Moisture increasing south of a warm front moved northward into western Texas. Instability increased east of a dry line, where thunderstorms were able to develop despite a strong cap. The thunderstorms moved east into western Oklahoma, but were fighting an even stronger cap as they moved east. The thunderstorms reached as far east as central Oklahoma before collapsing. Severe winds up to 70 mph and hail up to half-dollar size were reported with the thunderstorms. After the storms collapsed, they pushed out a gust front that had winds of 60 to 70 mph. Some damage was reported in and around the western sides of Oklahoma City.

Thunderstorm Wind in BECKHAM, OKLAHOMA
From 12-MAY-09 20:20:00 to 12-MAY-09 20:20:00 (CST-6)
Location: ELK CITY
Magnitude: 51.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

The wind gust was measured at the Elk City Regional Airport.

Thunderstorm Wind in BECKHAM, OKLAHOMA
From 12-MAY-09 20:05:00 to 12-MAY-09 20:06:00 (CST-6)
Location: SAYRE
Magnitude: 56.00 EG
Property damage: 3500.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Signs were blown onto Interstate 40 near exit 26. The west bound lanes had to be closed briefly as a result. Monetary damages were estimated.

Thunderstorm Wind in BECKHAM, OKLAHOMA
From 12-MAY-09 20:00:00 to 12-MAY-09 20:01:00 (CST-6)
Location: ERICK
Magnitude: 61.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Several two-inch diameter tree limbs were downed from one mile west of Erick to Erick. Monetary damages were estimated.

Hail in BECKHAM, OKLAHOMA
From 12-MAY-09 20:09:00 to 12-MAY-09 20:09:00 (CST-6)
Location: ERICK
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Quarter- to half dollar-size hail was reported.

Thunderstorm Wind in WASHITA, OKLAHOMA
From 12-MAY-09 20:40:00 to 12-MAY-09 20:41:00 (CST-6)
Location: FOSS
Magnitude: 61.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

An 18-wheeler jacknifed on Interstate 40 due to the strong winds. All lanes of traffic were blocked as a result. Monetary damages were estimated.

Thunderstorm Wind in TILLMAN, OKLAHOMA
From 12-MAY-09 20:55:00 to 12-MAY-09 20:55:00 (CST-6)
Location: TIPTON
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in JACKSON, OKLAHOMA
From 12-MAY-09 20:45:00 to 12-MAY-09 20:45:00 (CST-6)
Location: ALTUS
Magnitude: 51.00 MG
Crop damage: 0.00K
Reported by: Mesonet

A large gas station sign was blown down into the street in Altus. Power lines were also downed and minor roof damage was reported in Eldorado. Monetary damage estimates were not available.

Hail in TILLMAN, OKLAHOMA
From 12-MAY-09 21:26:00 to 12-MAY-09 21:26:00 (CST-6)
Location: HOLLISTER
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorm Wind in COMANCHE, OKLAHOMA
From 12-MAY-09 21:35:00 to 12-MAY-09 21:35:00 (CST-6)
Location: CHATTANOOGA
Magnitude: 57.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Hail in CADDO, OKLAHOMA
From 12-MAY-09 22:11:00 to 12-MAY-09 22:11:00 (CST-6)
Location: APACHE
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

High Wind in OKLAHOMA, OKLAHOMA
From 13-MAY-09 00:10:00 to 13-MAY-09 01:20:00 (CST-6)
Magnitude: 64.00 MG
Crop damage: 0.00K
Reported by: ASOS

Numerous non-thunderstorm wind gusts of 50 to 60 mph were reported, including gusts measured by the Oklahoma Mesonet, mainly over the western and northern sides of Oklahoma City. The highest gust measured was 74 mph at 124 am CDT near the Wiley Post Airport. Other peak gusts include 58 mph two miles east-northeast of Spencer, and 59 mph measured at the north Oklahoma City mesonet site. Damage was reported with the strong winds, mainly confined to tree limbs and power lines, although a tractor-trailer was blown over on Interstate 35, causing the road to be shut down for almost two hours. Power lines were downed along Memorial Road between Santa Fe Avenue and Western Avenue. Roof damage was reported at an apartment complex near Northwest Expressway and May Avenue. A tree was also blown onto a car near northeast 122nd and Council Road. The Farmer's Market at 63rd and May Avenue sustained damage to several tents that were bolted to the concrete. At the peak of the event, 5493 residences were without power. Monetary damage estimates were not available.

High Wind in LINCOLN, OKLAHOMA
From 13-MAY-09 00:00:00 to 13-MAY-09 02:30:00 (CST-6)
Magnitude: 61.00 EG
Crop damage: 0.00K
Reported by: Newspaper

Numerous non-thunderstorm wind gusts of 50 to 60 mph were reported near Prague, with peak gusts reaching as high as 70 mph. Damage included wooden fence paneling blown down and several tree limbs blown down. Monetary damage estimates were not available.

Thunderstorm Wind in GRADY, OKLAHOMA
From 12-MAY-09 22:32:00 to 12-MAY-09 22:32:00 (CST-6)
Location: CHICKASHA ARPT
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

The wind gust was measured at the Chickasha Airport.

High Wind in KINGFISHER, OKLAHOMA
From 12-MAY-09 22:45:00 to 12-MAY-09 23:10:00 (CST-6)
Magnitude: 51.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Numerous non-thunderstorm wind gusts over 50 mph were reported from between 1145 pm and 1210 am CDT.

High Wind in LOGAN, OKLAHOMA
From 12-MAY-09 23:35:00 to 12-MAY-09 23:55:00 (CST-6)
Magnitude: 53.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Numerous non-thunderstorm wind gusts over 50 mph were reported, with a peak gust of 61 mph measured at 1243 am CDT.

Hail in CADDO, OKLAHOMA
From 12-MAY-09 22:27:00 to 12-MAY-09 22:27:00 (CST-6)
Location: CYRIL
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Thunderstorm Wind in BECKHAM, OKLAHOMA
From 12-MAY-09 19:55:00 to 12-MAY-09 19:56:00 (CST-6)
Location: ERICK
Magnitude: 54.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet