A deep closed low along the California coast and broad upper level ridging centered over the southern Plains promoted deep southerly flow across the Desert Southwest. This southerly flow promoted anomalous moisture advection into the area with PWATs upwards of 1.8-2 in the Lower Colorado River Valley area. Abundant moisture combined with CAPE upwards of 1,500-2,000 J/kg and a weak shortwave embedded in the flow allowed for efficient rain-producing thunderstorms to develop heading into the early afternoon hours on the 2nd. Several rain gages recorded over an inch of rainfall with these thunderstorms across southwest Arizona while radar estimates indicated locally heavier amounts in excess of 1.5 in some areas. As a result of these thunderstorms producing very heavy rainfall amounts in a short period of time, numerous instances of flash flooding occurred, particularly in the Yuma, Quartzsite, and Bouse areas. A couple of water rescues occurred, but no injuries were reported during this event.

Flash Flood in LA PAZ, ARIZONA
From 02-SEP-23 19:12:00 to 02-SEP-23 20:12:00 (MST-7)
Location: QUARTZITE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Quartzsite Fire and Police performed a swift water rescue of two juveniles trapped on a small island in Tyson Wash. No injuries were reported.

Flash Flood in LA PAZ, ARIZONA
From 02-SEP-23 18:30:00 to 02-SEP-23 19:30:00 (MST-7)
Location: QUARTZITE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A low water crossing through Tyson Wash along Quail Trail Street was inundated by flash flooding, causing the road to be close. Timing was estimated based on the Tyson Wash stream gauge response on Main Street. No damage or injuries were reported.

Flash Flood in YUMA, ARIZONA
From 02-SEP-23 14:30:00 to 02-SEP-23 15:30:00 (MST-7)
Location: ARABY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

An image showed swift water flowing across 24th Street near South Avenue 5E, making the road impassable. No damage or injuries were reported.

Flash Flood in LA PAZ, ARIZONA
From 02-SEP-23 17:00:00 to 02-SEP-23 18:00:00 (MST-7)
Location: QUARTZSITE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

An image on social media showed elevated flow within Tyson Wash through La Paz Valley, making a low water crossing impassable. No damage or injuries were reported.

Flash Flood in LA PAZ, ARIZONA
From 02-SEP-23 15:30:00 to 02-SEP-23 16:30:00 (MST-7)
Location: VICKSBURG
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous washes along Highway 60 between mile markers 31-50 were flooded. Timing was estimated from radar. No damage or injuries were reported.

Flash Flood in LA PAZ, ARIZONA
From 02-SEP-23 18:12:00 to 02-SEP-23 18:42:00 (MST-7)
Location: QUARTZSITE ARPT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

A stream gauge along Tyson Wash in Quartzsite observed a rapid rise, reaching Action stage at 1812MST. As a result, low water crossings along the wash were inundated and made impassable. No damage or injuries were reported.

Flash Flood in LA PAZ, ARIZONA
From 02-SEP-23 14:15:00 to 02-SEP-23 18:15:00 (MST-7)
Location: BOUSE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

A stream gauge along Bouse Wash at Plomosa Road rose above Action stage around 1415MST, making low water crossings along the wash impassable. The wash remained above Action stage into the morning hours on the 3rd. No damage or injuries were reported.

Flash Flood in LA PAZ, ARIZONA
From 02-SEP-23 15:25:00 to 02-SEP-23 17:25:00 (MST-7)
Location: BOUSE
Flood cause: Heavy Rain
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Law Enforcement

A swift water rescue occurred after a single occupied vehicle attempted to drive through a flooded Bouse Wash low water crossing along Rabbit Lane near Stage Coach Road. No injuries were reported.

Flash Flood in YUMA, ARIZONA
From 02-SEP-23 13:34:00 to 02-SEP-23 15:34:00 (MST-7)
Location: EL PUEBLECITO
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Virginia Drive was closed between 24th Street and 28th Street due to flooding. No damage or injuries were reported.

Flash Flood in LA PAZ, ARIZONA
From 02-SEP-23 14:20:00 to 02-SEP-23 15:20:00 (MST-7)
Location: UTTING
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A video on social media showed a semi driving through a flooded low water crossing along SR 72 at Avenue 41 E with at least 6 inches of water flowing over the road. Timing was estimated from radar. No damage or injuries were reported.

Flash Flood in LA PAZ, ARIZONA
From 02-SEP-23 18:05:00 to 02-SEP-23 19:05:00 (MST-7)
Location: QUARTZSITE ARPT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A low water crossing through Tyson Wash along Kuehn Street was inundated by flash flooding, causing the road to be closed. Timing was estimated based on the stream gauge response located along Main Street. No damage or injuries were reported.

Flash Flood in YUMA, ARIZONA
From 02-SEP-23 15:34:00 to 02-SEP-23 19:34:00 (MST-7)
Location: ROLL NTLPE RANCH ARP
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Multiple washes were reported running in the Tacna area with one wash running at bankfull. Low water crossings east of Avenue 36 that run through the Gila River were reportedly closed due to flooding. During the event, a total of 2.04 of rain was observed within one hour in this area. No damage or injuries were reported.

Flash Flood in YUMA, ARIZONA
From 02-SEP-23 13:30:00 to 02-SEP-23 15:30:00 (MST-7)
Location: EL PUEBLECITO
Flood cause: Heavy Rain
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Public

Images and videos showed a substantial amount of standing water along Madison Avenue near 23rd Street, impacting travel in the area. A car reportedly stalled in this intersection and had to be pushed out. Nearby in the intersection of 17th Street and 1st Avenue, video showed another stalled car having to be pulled out of the flooded roadway. No injuries were reported.

Flood in LA PAZ, ARIZONA
From 02-SEP-23 18:15:00 to 03-SEP-23 07:30:00 (MST-7)
Location: BOUSE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

A stream gauge located along Bouse Wash at Plomosa Road initially rose above Action stage around 1415MST as a result of flash flooding. The wash crested near moderate flood stage at 2150MST before eventually falling back below Action stage around 0730MST on the 3rd. No damage or injuries were reported.