A backdoor cold front acted on a warm and moist air mass to produce severe thunderstorms.  Wet microbursts and flash flooding were the results.

Lightning in PIMA, ARIZONA
From 24-AUG-10 15:00:00 to 24-AUG-10 15:00:00 (MST-7)
Location: TUCSON
Property damage: 0.50K
Crop damage: 0.00K
Reported by: Newspaper

Lightning struck a palm tree at the Randolph Community Center. A fire was ignited, which spread to surrounding brush, prompting the evacuation of the center.

Thunderstorm Wind in COCHISE, ARIZONA
From 24-AUG-10 17:05:00 to 24-AUG-10 17:20:00 (MST-7)
Location: HUACHCA VISTA
Magnitude: 52.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Local Law Enforcement reported several trees and power lines down after thunderstorms moved through Whetstone.

Lightning in PIMA, ARIZONA
From 24-AUG-10 18:15:00 to 24-AUG-10 18:15:00 (MST-7)
Location: ORO VLY
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Broadcast Media

After a majority of the thunderstorm activity had started to wind down, lightning struck a house in Oro Valley.  The house then caught fire causing extensive damage.

Thunderstorm Wind in PIMA, ARIZONA
From 24-AUG-10 16:00:00 to 24-AUG-10 16:55:00 (MST-7)
Location: TUCSON
Magnitude: 55.00 MG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: ASOS

Severe thunderstorms redeveloped over central Tucson, moved westward and generated high winds causing a car port to collapse in midtown Tucson and a 63 mph wind gust to be recorded at Ryan Air Field.

Thunderstorm Wind in PINAL, ARIZONA
From 24-AUG-10 14:35:00 to 24-AUG-10 14:35:00 (MST-7)
Location: FLORENCE
Magnitude: 50.00 EG
Property damage: 0.10K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm winds downed tree limbs.

Flash Flood in COCHISE, ARIZONA
From 24-AUG-10 22:00:00 to 24-AUG-10 23:00:00 (MST-7)
Location: SUNNYSIDE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorms dropped heavy rain with amounts ranging from 1 inch up to 3.5 inches, causing numerous streets to flood in Sierra Vista. In addition, the Hereford Road Bridge at the San Pedro River was closed due to flooding.

Thunderstorm Wind in PIMA, ARIZONA
From 24-AUG-10 15:00:00 to 24-AUG-10 15:30:00 (MST-7)
Location: SABINO
Magnitude: 55.00 EG
Property damage: 85.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Thunderstorms developed over eastern portions of the Tucson area around 2:30 pm MST.  Storms slowly moved to the east at around 5 to 10 mph dropping heavy rainfall and putting out thunderstorm winds in excess of 60 mph.  The first reports of damage were received at 3 pm on the east side of Tucson.  Several tree limbs were downed on Columbus Blvd, with a few power poles down on 6th street.  At 3:09 pm, reports were received of several street signs down in the La Paloma Estates.  By 3:15 pm, reports were coming in from the media about several roofs damaged in eastern sections of Tucson. Also around 3:15 pm, spotters reported several large trees downed in east Tucson, including trees down on 22nd St and Broadway Blvd. A large was blown into an election polling station building near S. Alvernon and E. Benson Highways in southern Tucson.

Flash Flood in PIMA, ARIZONA
From 24-AUG-10 15:20:00 to 24-AUG-10 18:30:00 (MST-7)
Location: TUSCON RYAN FLD ARPT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorms produced heavy rain of up to 2 inches across portions of the Tucson metro area. Heavy rains resulted in a vehicle stalling in rising water at the intersection of Tucson Blvd. and Elm Street at 3:20 pm. By 4:00 pm, numerous streets were flooding near the University of Arizona campus in Tucson. Heavy rains falling near Ryan Field Airport resulted numerous washes flooding into residential neighborhoods.  At 6:00 pm, firefighters pulled an 11 year old boy out of Alamo Wash near Tucson Medical Center.

Flash Flood in GRAHAM, ARIZONA
From 24-AUG-10 18:15:00 to 24-AUG-10 20:00:00 (MST-7)
Location: FT GRANT
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Local law enforcement reported that Highway 191 between Safford and Interstate 10 had been closed due to flooding.  At 7:00 pm, a spotter located in southern portions of Safford reported that he had received just over 3 inches of rainfall and that a majority of surrounding roads were impassable due to street flooding.  According to Thatcher Police, a few homes near the Eastern Arizona College had water seep into their garages, one apartment suffered water damage, and the back room of a home on Fourth Avenue had water running into it.  Also, a home south of Safford reported flood damage, and the Highway Department closed Safford/Bryce Road from Eighth Ave. to Bryce Eden Road due to flooding and debris.  A vehicle also stalled in running water on Quattro Cerros Road near the Artesia area south of Safford.  Water was running through the vehicle, but two passengers were able to get out.  There were also several other reports of washed out roads and drainage problems.

Thunderstorm Wind in COCHISE, ARIZONA
From 24-AUG-10 16:15:00 to 24-AUG-10 17:00:00 (MST-7)
Location: BENSON
Magnitude: 61.00 EG
Property damage: 1.00M
Crop damage: 0.00K
Reported by: Newspaper

The Benson News-Sun and a local city official reported extensive damage to much of the city of Benson from thunderstorm activity. The city official reported numerous mature and young trees uprooted, street signs bent or pulled completely out of the ground, damage to dwellings from uprooted trees, small sheds and car ports were lifted and thrown 50-75 feet, and shingle damage to numerous homes. Also, property fences were knocked over, camper trailers were turned over, and numerous power outages.  The newspaper added that one particular insurance provider received 40 claims from residents, mostly related to roof damage. Additional information from the newspaper stated that at least 80 street signs had to be replaced.  Extensive damage was also done to the Turquoise Hills Golf Course where numerous large trees were downed and buildings damaged.

Thunderstorm Wind in PINAL, ARIZONA
From 24-AUG-10 15:22:00 to 24-AUG-10 15:22:00 (MST-7)
Location: ORACLE
Magnitude: 52.00 EG
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorms moving into Oracle resulted in trees and power lines downed across a roadway.  The most extensive damage was a roof blown off of a home located on Bonito Drive in Oracle.

Flash Flood in COCHISE, ARIZONA
From 24-AUG-10 16:15:00 to 24-AUG-10 17:45:00 (MST-7)
Location: BENSON
Flood cause: Heavy Rain
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Newspaper

The Benson News-Sun reported that a man was pulled from a running wash after he attempted to drive through 2 feet of running water on an adjacent street.  The force of the water on the street carried his car into the wash and up against a concrete wall.  The driver then attempted to get out of the vehicle, but fell 10-15 feet down into the wash underneath his car.  Fire crews were able to quickly rescue the driver.  He was escorted to the local hospital.  City officials also reported numerous washes flooding neighborhood streets.

Lightning in COCHISE, ARIZONA
From 24-AUG-10 16:15:00 to 24-AUG-10 17:00:00 (MST-7)
Location: BENSON
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Newspaper

The Benson News-Sun reported several lightning strikes causing damage and fires in and around Benson.  The most extensive lightning damage was done to two motors at the waste water treatment facility.  Lightning also damaged numerous transformers.