A large cluster of very strong thunderstorms moved steadily north and across the west and northwest portions of the greater Phoenix area, including communities of Sun City and Surprise, during the evening hours on August 2nd. The more intense thunderstorms managed to produce unusually heavy amounts of rainfall; there was a confirmed report of 2.9 inches measured in the town of Surprise. Large hail also was reported in the area with diameters in excess of one inch. In addition, some of the storms generated very strong and gusty outflow winds well in excess of 60 mph. The winds downed numerous trees in the vicinity of the Loop 303 and West Bell Road, and also cracked windows in some homes. Despite the intense rainfall, flash flooding was not reported; there were instances of street flooding and an Urban and Small Stream Flood Advisory was issued for the area as a result.

Thunderstorm Wind in MARICOPA, ARIZONA
From 02-AUG-18 18:45:00 to 02-AUG-18 19:30:00 (MST-7)
Location: BEARDSLEY
Magnitude: 61.00 EG
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A large cluster of thunderstorms moved steadily north and across the western portion of the greater Phoenix area during the evening hours on August 2nd. Some of the stronger storms generated gusty damaging outflow winds that affected communities such as Sun City West and Waddell. According to a trained weather spotter located about 2 miles southwest of Sun City West, at 1845MST gusty winds estimated to be as high as 70 mph downed about 20 trees with diameters of 3 to 4 inches. Several larger trees with 8 inch diameter trunks were also downed. The downed trees were located along Bell Road between Litchfield and Reems Roads. Between 1845MST and 1930MST, multiple reports of downed trees were received from the public as well as trained spotters; most of the reports were near Bell Road between the Loop 303 and Litchfield road.

Thunderstorm Wind in MARICOPA, ARIZONA
From 02-AUG-18 19:53:00 to 02-AUG-18 19:55:00 (MST-7)
Location: WITTMANN
Magnitude: 52.00 EG
Property damage: 0.50K
Crop damage: 0.00K
Reported by: Trained Spotter

A large cluster of intense thunderstorms moved north through the western portion of the greater Phoenix area during the evening hours on August 2nd. Some of the stronger storms produced gusty and damaging outflow winds and affected areas around the community of Wittmann. A trained weather spotter reported that a wind gust, estimated to be about 60 mph in strength, snapped a branch off of one of his trees. The branch had a diameter of 5 inches.

Thunderstorm Wind in MARICOPA, ARIZONA
From 02-AUG-18 18:48:00 to 02-AUG-18 18:50:00 (MST-7)
Location: WADDELL
Magnitude: 56.00 EG
Property damage: 4.00K
Crop damage: 0.00K
Reported by: Public

A cluster of very strong thunderstorms moved steadily north and across the western portion of the greater Phoenix area during the evening hours on August 2nd. Some of the more intense storms produced gusty and damaging outflow winds that affected communities such as Waddell and Surprise. According to a report from the public, about 2 miles northwest of Waddell and just west of Surprise, strong outflow winds downed several trees and cracked the window in one of the homes in the area. Wind gusts were estimated to be as high as 65 mph. No injuries were reported.

Hail in MARICOPA, ARIZONA
From 02-AUG-18 18:55:00 to 02-AUG-18 18:55:00 (MST-7)
Location: WADDELL
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A cluster of strong thunderstorms moved north across the western portion of the greater Phoenix area during the evening hours on August 2nd. A few of the more intense storms generated large hail and affected areas west of the Loop 303 highway and along Bell Road. According to a trained spotter, large hail was measured about 4 miles northwest of Waddell, to the west of the Loop 303 highway and along Bell Road. The hailstones had a diameter of around one inch. No damaged was reported due to the large hail.

Hail in MARICOPA, ARIZONA
From 02-AUG-18 19:20:00 to 02-AUG-18 19:20:00 (MST-7)
Location: WADDELL
Magnitude: 0.88 
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Public

A cluster of strong thunderstorms moved steadily north across the western portion of the greater Phoenix area during the evening hours on August 2nd. Some of the stronger storms generated large hail in addition to intense rainfall. According to a report received from the public, large hail fell about 3 miles northwest of Waddell, near the intersection of Cotton Road and Bell Road, just west of the Loop 303 highway. At least one of the hailstones had a diameter measured to be 0.88 inches. At the same time of the hail, a downburst occurred that blew down 2 trees.

Thunderstorm Wind in MARICOPA, ARIZONA
From 02-AUG-18 18:45:00 to 02-AUG-18 18:45:00 (MST-7)
Location: WADDELL
Magnitude: 61.00 EG
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Public

A large cluster of very strong thunderstorms moved steadily to the north across the western portion of the greater Phoenix area during the evening hours on August 2nd. Some of the storms affected homes from the town of Surprise westward past the Loop 303 highway. The more intense thunderstorms generated damaging outflow winds; according to a public report gusty microburst winds estimated to be at least 70 mph in strength generated minor to moderate roof damage to many houses in a subdivision located north of Bell Road and west of the Loop 303. The homes were located just to the southeast of Arizona Traditions Golf Club.

Heavy Rain in MARICOPA, ARIZONA
From 02-AUG-18 19:45:00 to 02-AUG-18 22:30:00 (MST-7)
Location: WADDELL
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A cluster of very strong thunderstorms moved steadily north across the western portion of the greater Phoenix area during the evening hours on August 2nd. Some of the stronger storms produced intense rainfall with peak rain rates well in excess of one inch per hour. The heavy rains led to local street flooding west of Surprise and near Sun City West, especially along Bell Road. According to a trained weather spotter, at 1915MST very heavy rain was measured along Bell Road just to the east of the Loop 303 highway. 2.05 inches of rain was measured in the area. Downbursts accompanied the heavy rain which caused trees in the area to be downed. Heavy rain led to street flooding and the Surprise Police Department closed Sunrise Boulevard at Bell Road due to water across the road. An Urban and Small Stream Flood Advisory was issued for the area at 1934MST and it remained in effect until 2230MST. There were other heavy rain reports in the area, based on CocoRAHS weather station observations. One such station to the southeast of the Loop 303 and Bell Road intersection measured 1.18 inches of rain. The most significant report came from another CocoRAHS station in Surprise that measured a storm total rainfall of 2.90 inches. The station ID was AZ-MR-42. There were no flash flooding reports in Surprise, despite the very heavy rainfall that occurred.