An upper level low along the southern California coast spread moisture into south central Arizona on the 10th. This led to scattered afternoon and evening thunderstorms, with the strongest storms located to the east of Central Phoenix. The storms produced gusty damaging winds in excess of 60 mph. Large hail and dense blowing dust also occurred across the lower south central deserts.

Thunderstorm Wind in MARICOPA, ARIZONA
From 10-SEP-11 17:55:00 to 10-SEP-11 17:55:00 (MST-7)
Location: TWIN KNOLLS
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Strong thunderstorms developed across the eastern portion of the greater Phoenix area during the evening hours on September 10th. At approximately 6 pm, a National Weather Service employee in east Mesa estimated a thunderstorm wind gust to 70 mph. No damage was reported with this gust.

Thunderstorm Wind in MARICOPA, ARIZONA
From 10-SEP-11 18:02:00 to 10-SEP-11 18:02:00 (MST-7)
Location: TWIN KNOLLS
Magnitude: 61.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Strong thunderstorms with damaging microburst winds affected part of the eastern Phoenix metropolitan area during the evening hours on September 10th. A trained weather spotter, near Brown and Ellsworth roads in east Mesa, reported that trees were downed due to winds estimated at 70 mph.

Thunderstorm Wind in MARICOPA, ARIZONA
From 10-SEP-11 19:50:00 to 10-SEP-11 19:50:00 (MST-7)
Location: SCOTTSDALE MUNI
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorms with strong gusty winds moved across eastern portions of the greater Phoenix area during the evening hours on September 10th. A trained weather spotter, located about 5 miles northeast of Paradise Valley, estimated a peak wind gust to 60 mph. No damage was reported with this wind gust.

Thunderstorm Wind in PINAL, ARIZONA
From 10-SEP-11 18:30:00 to 10-SEP-11 18:35:00 (MST-7)
Location: FLORENCE
Magnitude: 55.00 EG
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorms with damaging microburst winds moved across the Florence area during the evening hours on September 10th. A trained weather spotter in northeast Florence reported roof damage to several carports. Winds were estimated to be in excess of 50 knots.

Thunderstorm Wind in MARICOPA, ARIZONA
From 10-SEP-11 18:00:00 to 10-SEP-11 18:02:00 (MST-7)
Location: GOLDEN HILLS
Magnitude: 60.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Scattered thunderstorms with strong damaging winds moved across eastern portions of the greater Phoenix area during the evening hours on September 10th. According to reports from local broadcast media, 7 power poles were downed in the city of Mesa at the intersection of University Drive and 70th Street. Winds were estimated to be near 60 knots.

Thunderstorm Wind in MARICOPA, ARIZONA
From 10-SEP-11 20:00:00 to 10-SEP-11 20:30:00 (MST-7)
Location: SUN LAKES
Magnitude: 50.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Scattered thunderstorms with strong damaging wind moved across the eastern greater Phoenix area during the evening hours on September 10th. At 830 pm a trained weather spotter in Chandler reported that several tree branches as large as 9 inches in diameter were broken off by strong wind. At approximately 8 pm, local media reported a number of trees down in northeast Gilbert, between Elliot and Baseline roads on Val Vista.

Hail in MARICOPA, ARIZONA
From 10-SEP-11 17:55:00 to 10-SEP-11 17:55:00 (MST-7)
Location: TWIN KNOLLS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Strong thunderstorms moved across the eastern greater Phoenix area during the evening hours on September 10th, and some of them produced large hail. A National Weather Service employee in east Mesa reported hail estimated to be one inch in diameter. No damage was reported in association with the large hail.

Thunderstorm Wind in MARICOPA, ARIZONA
From 10-SEP-11 19:30:00 to 10-SEP-11 19:35:00 (MST-7)
Location: CAVE CREEK
Magnitude: 50.00 EG
Property damage: 12.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Strong thunderstorms with damaging winds moved across the northeastern portions of the greater Phoenix area during the evening hours on September 10th. A trained weather spotter reported that numerous large tree branches were blown down near the intersection of Scottsdale road and Westland Road, a few miles south of Carefree. Winds were estimated to be in excess of 50 knots.

Thunderstorm Wind in MARICOPA, ARIZONA
From 10-SEP-11 17:50:00 to 10-SEP-11 17:52:00 (MST-7)
Location: BUCKHORN
Magnitude: 60.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Scattered thunderstorms with strong and damaging winds moved across the eastern portions of the greater Phoenix area during the evening hours on September 10th. According to a National Weather Service storm survey in Mesa, winds estimated to be at least 60 knots downed multiple trees with diameters up to 14 inches. In addition, the winds caused shingle damage to area homes.

Dust Storm in CENTRAL DESERTS, ARIZONA
From 10-SEP-11 19:00:00 to 10-SEP-11 20:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Strong thunderstorms developed across northwest Pinal county during the evening hours on September 10th. Gusty outflow winds from the thunderstorms generated a dust storm over portions of the county, including the corridor from Casa Grande through Maricopa. Several trained weather spotters reported visibility at or below one quarter mile in blowing dust. At 709 pm, a spotter in Casa Grande reported visibility less than 1/8 of a mile in a dust storm.