Scattered thunderstorms develooped across the higher terrain of southeastern Arizona during the afternoon hours on July 21st. The storms then moved towards the northwest and into south central Arizona, including the greater Phoenix area, during the late afternoon and early evening. Some of the stronger thunderstorms produced strong, gusty and damaging outflow winds, in addition to locally heavy rainfall. Significant flash flooding did not occur, but urban flooding of streets and washes was observed.

Thunderstorm Wind in MARICOPA, ARIZONA
From 21-JUL-12 17:45:00 to 21-JUL-12 17:50:00 (MST-7)
Location: BUCKHORN
Magnitude: 60.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Scattered strong thunderstorms developed across southeast Arizona during the afternoon hours on July 21st. They generated strong gusty outflow winds in excess of 40 mph which moved into the greater Phoenix area during the late afternoon and produced dense blowing dust. Some of the storms then moved into the southeast portions of the greater Phoenix area and produced strong, damaging microburst winds which enhanced the earlier outflow winds. A trained weather spotter in far East Mesa reported a variety of wind damage at approximately 545 pm. He reported damage to an awning, a carport taken off by wind, windows blown out and cactus trees blown over.

Thunderstorm Wind in MARICOPA, ARIZONA
From 21-JUL-12 19:10:00 to 21-JUL-12 19:10:00 (MST-7)
Location: PHOENIX DEER VLY ARP
Magnitude: 60.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Public

Scattered thunderstorms moved into the greater Phoenix metropolitan area during the evening hours on July 21st. The storms were accompanied by strong gusty outflow winds, and dense blowing dust. Some of the storms generated damaging microburst winds as well. At 710 pm, there was a public report of 2 trees downed by wind about 6 miles east of Peoria. The wind gusts were estimated to be about 60 knots, and the trees were rather large with diameters of 12 inches.

Thunderstorm Wind in GILA, ARIZONA
From 21-JUL-12 16:15:00 to 21-JUL-12 16:15:00 (MST-7)
Location: ROOSEVELT GRPVN ARPT
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Scattered thunderstorms moved through south central Arizona during the afternoon hours on July 21st, and some of them produced gusty and damaging microburst winds. According to a trained weather spotter 6 miles east of the Tonto National Monument, at 415 pm thunderstorm winds estimated at 60 mph uprooted a 20 inch diameter Mulberry tree. In addition, the strong winds tore metal off of a storage shed and ripped some shingles off of a nearby roof.

Thunderstorm Wind in PINAL, ARIZONA
From 21-JUL-12 17:00:00 to 21-JUL-12 17:00:00 (MST-7)
Location: APACHE JCT
Magnitude: 35.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Scattered thunderstorms developed over the higher terrain of southeast Arizona during the afternoon hours, then moved towards the northwest and into the greater Phoenix area by late afternoon. In addition to generating dense blowing dust, the storms also created strong, gusty and damaging outflow winds. At 5 pm, a trained weather spotter 2 miles west of Apache Junction reported that strong winds had ripped a number of shingles off of his roof. He estimated the wind gusts to be at least 40 mph.

Thunderstorm Wind in MARICOPA, ARIZONA
From 21-JUL-12 17:11:00 to 21-JUL-12 17:11:00 (MST-7)
Location: WEST CHANDLER
Magnitude: 55.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Scattered thunderstorms developed to the southeast of the greater Phoenix area during the afternoon hours on July 21st. The storms produced strong and gusty outflow winds which moved northwest and into the Phoenix metropolitan area during the late afternoon. The winds, which were in excess of 50 mph at times, generated dense blowing dust and dust storm conditions. At 511 pm, a trained weather spotter 2 miles southwest of Firebird Lake, or in far southwest Chandler, measured a wind gust to 63 mph. At the time, a dust storm was in progress with zero visibility in dense blowing dust.

Thunderstorm Wind in MARICOPA, ARIZONA
From 21-JUL-12 17:55:00 to 21-JUL-12 17:55:00 (MST-7)
Location: (CHD)WILLIAMS AFB
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Strong thunderstorms developed over southeast Arizona during the afternoon hours on July 21st, and they generated strong and gusty outflow winds which moved to the northwest and into the greater Phoenix area in the late afternoon. At 555 pm, the KIWA AWOS weather station at Phoenix Mesa-Gateway Airport recorded a measured wind gust to 52 knots.

Heavy Rain in MARICOPA, ARIZONA
From 21-JUL-12 19:30:00 to 21-JUL-12 21:00:00 (MST-7)
Location: PHOENIX DEER VLY ARP
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Scattered thunderstorms developed across southeast Arizona during the afternoon hours on July 21st and they spread northwestward and into the greater Phoenix area during the evening hours. In addition to strong gusty winds and dense blowing dust, some of the storms produced locally heavy rainfall which led to urban flooding.  At 745 pm a trained spotter 6 miles east of Peoria reported heavy rain which caused local washes to run and curb to curb street flooding. In addition, a local retention basin had filled up due to the heavy rainfall.