A large thunderstorm complex developed and tracked into south-central Arizona during the early morning hours on the 4th with widespread heavy rainfall activity across the Phoenix area, leading to flash flooding. The thunderstorm complex continued to track westward through southwest Arizona and into the Lower Colorado River Valley through the morning hours while at the same time weakening in the process.

Flash Flood in MARICOPA, ARIZONA
From 04-AUG-22 05:04:00 to 04-AUG-22 07:04:00 (MST-7)
Location: PHOENIX TURF ARPT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

ADOT webcams showed flooding at the I-17 and Greenway Road underpass, making the road impassable. Flooding was also reported at the I-17 and Thunderbird Road underpass. No damage or injuries were reported.

Flash Flood in MARICOPA, ARIZONA
From 04-AUG-22 05:15:00 to 04-AUG-22 06:15:00 (MST-7)
Location: CACTUS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Multiple videos and pictures on social media showed Dreamy Draw Wash flowing across low water crossings near 12th Street and Kaler Drive as well as 14th Street and Desert Park Lane. No damage or injuries were reported.

Flash Flood in LA PAZ, ARIZONA
From 04-AUG-22 07:50:00 to 04-AUG-22 08:50:00 (MST-7)
Location: BOUSE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

ADOT reported that SR 72 at milepost 30 near Bouse was closed due to flooding. No damage or injuries were reported. Timing was estimated from radar.

Lightning in MARICOPA, ARIZONA
From 04-AUG-22 04:54:00 to 04-AUG-22 04:54:00 (MST-7)
Location: (PHX)SKY HARBOR ARPT
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Lightning was reported to have struck a generator at Phoenix Sky Harbor International Airport, causing a server to go down and delay dozens of Southwest Airlines' flights for several hours. No injuries were reported.

Flash Flood in MARICOPA, ARIZONA
From 04-AUG-22 05:30:00 to 04-AUG-22 06:30:00 (MST-7)
Location: PHOENIX
Flood cause: Heavy Rain
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

Video showed I-17 southbound at Indian School Road under about a foot of water with law enforcement having to push a stalled vehicle out. No injuries were reported.

Flash Flood in MARICOPA, ARIZONA
From 04-AUG-22 05:45:00 to 04-AUG-22 06:15:00 (MST-7)
Location: PHOENIX TURF ARPT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: County Official

The Maricopa County Flood Control District streamflow gage along East Fork Cave Creek exceeded alarm stage, peaking at a height of 2.15 feet and a flow of 473 cfs and impacting a downstream low water crossing along 7th Avenue. No damage or injuries were reported.

Flash Flood in MARICOPA, ARIZONA
From 04-AUG-22 05:20:00 to 04-AUG-22 06:20:00 (MST-7)
Location: PARADISE VLY
Flood cause: Heavy Rain
Property damage: 0.50K
Crop damage: 0.00K
Reported by: Public

A video on social media showed a large amount of mud and rock debris across a low water crossing along Onyx Avenue near 42nd Street, indicating high flow in Tatum Wash earlier in the morning had made the road impassable. Further downstream along 40th Street near Mission Lane, another video indicated flow in the wash climbed high enough to overtop a bridge, partially pushing a guardrail over and leaving mud and small debris on the bridge. No injuries were reported.

Heavy Rain in MARICOPA, ARIZONA
From 04-AUG-22 05:10:00 to 04-AUG-22 05:10:00 (MST-7)
Location: GLENDALE MUNI ARPT
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Heavy rain caused a portion of the roof to collapse at Bashas near 75th Ave and Thunderbird Rd in Peoria. No injuries were reported. Timing estimated from radar.