A weakening inverted trough over northern Sonora along with an upper level jet positioned along the West Coast provided the necessary forcing needed to get thunderstorm development during the afternoon and evening across southeast California on the 30th. Deep moisture in place allowed for thunderstorms to produce locally heavy rainfall, which resulted in multiple instances of flash flooding. Some thunderstorms became strong to severe, leading to isolated cases of damaging wind gusts and localized dense blowing dust. One injury was reported after two tractor trailers were blown over along Interstate 10 several miles east of Chiriaco Summit by strong outflow winds from nearby thunderstorms.

Flash Flood in RIVERSIDE, CALIFORNIA
From 30-JUL-21 19:29:00 to 30-JUL-21 20:29:00 (PST-8)
Location: CHIRIACO SUMMIT
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Cal Fire/Riverside County Fire Department reported that a vehicle was trapped in flowing water approximately 3 feet deep on Power Line Road near the I-10 Red Cloud Mine Road exit. Two occupants and a dog were rescued from the vehicle with no injuries reported.

Dust Storm in IMPERIAL VALLEY, CALIFORNIA
From 30-JUL-21 16:52:00 to 30-JUL-21 17:02:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained weather spotter reported near-zero visibility on I-8 at Forrester Road due to dense blowing dust. Gusty outflow winds from nearby thunderstorms was the cause of the dense blowing dust. No damage or injuries were reported.

Thunderstorm Wind in RIVERSIDE, CALIFORNIA
From 30-JUL-21 17:06:00 to 30-JUL-21 17:16:00 (PST-8)
Location: CHIRIACO SUMMIT
Magnitude: 50.00 EG
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported that two tractor trailers were blown over on an Interstate 10 ramp several miles east of Chiriaco Summit by strong winds from thunderstorms. One injury was reported.

Flash Flood in RIVERSIDE, CALIFORNIA
From 30-JUL-21 17:15:00 to 30-JUL-21 18:15:00 (PST-8)
Location: CACTUS CITY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A video on social media showed several inches of water across the roadway along Park Boulevard and Pinto Basin Road in Joshua Tree National Park, impeding travel. The owner of the video reported that there was heavy flooding and roads washed out in multiple locations from the north entrance of the park to the south entrance. The location was approximated from the report in combination with known areas with low water crossings and flood prone areas along Park Boulevard and Pinto Basin Road. No damage or injuries were reported.

Flash Flood in IMPERIAL, CALIFORNIA
From 30-JUL-21 18:02:00 to 30-JUL-21 19:02:00 (PST-8)
Location: OGILBY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported that Ogilby Road between I-8 and SR 78 was closed due to flooding. No damage or injuries were reported.

Flash Flood in IMPERIAL, CALIFORNIA
From 30-JUL-21 18:53:00 to 30-JUL-21 19:53:00 (PST-8)
Location: ARAZ
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported that Araz Road at I-8 was closed due to flooding. No damage or injuries were reported.