Eastern Pacific Hurricane Hilary made landfall on the Baja Peninsula early on the morning of the 20th and reached Southern California as a tropical storm that afternoon. The cyclone brought widespread flash flooding to southeast California, along with isolated high winds.

Flash Flood in INYO, CALIFORNIA
From 19-AUG-23 12:02:00 to 19-AUG-23 14:00:00 (PST-8)
Location: DARWIN
Flood cause: Heavy Rain / Tropical System
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Water and debris flooded Highway 190 between mile markers 45 and 46.

Flash Flood in INYO, CALIFORNIA
From 19-AUG-23 13:22:00 to 20-AUG-23 17:00:00 (PST-8)
Location: KEELER
Flood cause: Heavy Rain / Tropical System
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The intersection of Highways 190 and 136 was washed out. The road remained closed and intermittently flooded for over a day.

Flash Flood in INYO, CALIFORNIA
From 19-AUG-23 14:07:00 to 19-AUG-23 16:00:00 (PST-8)
Location: BARTLETT
Flood cause: Heavy Rain / Tropical System
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Highway 395 flooded both in Lone Pine and at Boulder Creek 4 miles SSE of Lone Pine.

Flash Flood in INYO, CALIFORNIA
From 19-AUG-23 15:57:00 to 19-AUG-23 17:30:00 (PST-8)
Location: HARRISBURG
Flood cause: Heavy Rain / Tropical System
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Rocks and debris blocked Highway 190 at Towne Pass.

Flood in INYO, CALIFORNIA
From 20-AUG-23 09:30:00 to 20-AUG-23 14:30:00 (PST-8)
Location: DEATH VLY JCT
Flood cause: Heavy Rain / Tropical System
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

A large pool of standing water covered the intersection of Highways 190 and 127 for several hours.

Flash Flood in INYO, CALIFORNIA
From 20-AUG-23 10:00:00 to 21-AUG-23 08:00:00 (PST-8)
Location: DEEP SPGS
Flood cause: Heavy Rain / Tropical System
Property damage: 500.00M
Crop damage: 0.00K
Reported by: Park/Forest Service

Major flash flooding occurred throughout Death Valley National Park. Four hundred miles of NPS roads were damaged or destroyed, in addition to other roads maintained by the county and state. About 1000 feet of fresh water lines were destroyed at Furnace Creek. Damage to most structures was minimized or prevented by berms and other protections. The exact start and end times are unknown.

Lightning in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 12:00:00 to 20-AUG-23 12:00:00 (PST-8)
Location: BARSTOW
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Public

Lightning struck a utility pole next to I-15, closing the highway for a period.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 12:00:00 to 20-AUG-23 23:59:00 (PST-8)
Location: CRUCERO
Flood cause: Heavy Rain / Tropical System
Property damage: 1.00M
Crop damage: 0.00K
Reported by: Park/Forest Service

Flash flooding occurred throughout the Mojave National Preserve. All roads, facilities, trails, etc in the preserve were closed. Exact start and end times unknown.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 14:13:00 to 20-AUG-23 16:00:00 (PST-8)
Location: (NXP)MCAF TWENTYNINE
Flood cause: Heavy Rain / Tropical System
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Heavy flooding pushed debris across Highway 62 between Cactus Jack and Godwin.

High Wind in CADIZ BASIN, CALIFORNIA
From 20-AUG-23 14:30:00 to 20-AUG-23 15:50:00 (PST-8)
Magnitude: 72.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

These winds occurred 10 miles SSE of Essex.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 15:01:00 to 20-AUG-23 16:30:00 (PST-8)
Location: JOSHUA TREE
Flood cause: Heavy Rain / Tropical System
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Department of Highways

Mud and debris washed onto Highway 62 just east of Olympic Rd.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 16:00:00 to 20-AUG-23 18:00:00 (PST-8)
Location: TWENTY NINE PALMS
Flood cause: Heavy Rain / Tropical System
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Several roads in Twentynine Palms were closed due to flooding.

High Wind in MORONGO BASIN, CALIFORNIA
From 20-AUG-23 16:15:00 to 20-AUG-23 16:56:00 (PST-8)
Magnitude: 51.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 17:13:00 to 20-AUG-23 19:00:00 (PST-8)
Location: MORONGO LODGE
Flood cause: Heavy Rain / Tropical System
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

A boulder washed onto Highway 62 at Hess Rd.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 17:37:00 to 20-AUG-23 20:00:00 (PST-8)
Location: BAKER
Flood cause: Heavy Rain / Tropical System
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Flash flooding in Baker was up to vehicle hoods.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 17:48:00 to 20-AUG-23 20:00:00 (PST-8)
Location: VIDAL JCT ARPT
Flood cause: Heavy Rain / Tropical System
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Highway 95 was flooded near mile marker 17.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 17:52:00 to 20-AUG-23 20:00:00 (PST-8)
Location: WESTEND
Flood cause: Heavy Rain / Tropical System
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The intersection of Highway 178 and Trona Rd was flooded with multiple vehicles stuck, and 178 was also possibly washed out at Pinnacle Rd.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 18:19:00 to 20-AUG-23 20:30:00 (PST-8)
Location: YUCCA VLY ARPT
Flood cause: Heavy Rain / Tropical System
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Water and mud covered La Contenta and Alta Loma Rds.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 18:40:00 to 20-AUG-23 21:00:00 (PST-8)
Location: BAKER
Flood cause: Heavy Rain / Tropical System
Property damage: 1.00M
Crop damage: 0.00K
Reported by: Law Enforcement

Four feet of rushing water trapped people in their cars on Highway 127. The road was severely damaged.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 18:46:00 to 20-AUG-23 20:00:00 (PST-8)
Location: (NXP)MCAF TWENTYNINE
Flood cause: Heavy Rain / Tropical System
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Mud and debris covered the intersection of Amboy Rd and Cactus Jack.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 19:18:00 to 20-AUG-23 21:00:00 (PST-8)
Location: RED MTN
Flood cause: Heavy Rain / Tropical System
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The intersection of Highway 395 and Randsburg Cutoff Rd was flooded.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 19:33:00 to 20-AUG-23 21:00:00 (PST-8)
Location: DAGGETT
Flood cause: Heavy Rain / Tropical System
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Fast-moving water covered the intersection of I-15 and Fort Irwin Rd.

High Wind in MORONGO BASIN, CALIFORNIA
From 20-AUG-23 21:05:00 to 20-AUG-23 21:05:00 (PST-8)
Magnitude: 57.00 MG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

This gust blew part of the roof off of a house 2 miles WSW of Twentynine Palms.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 22:19:00 to 20-AUG-23 23:59:00 (PST-8)
Location: PIONEERTOWN
Flood cause: Heavy Rain / Tropical System
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Highway 247 was flooded and closed at Pipes Canyon Rd.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 23:19:00 to 21-AUG-23 01:00:00 (PST-8)
Location: MORONGO LODGE
Flood cause: Heavy Rain / Tropical System
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

A vehicle was covered in mud and sinking at the intersection of Covington Dr and East Dr.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 20-AUG-23 23:56:00 to 21-AUG-23 02:00:00 (PST-8)
Location: MORONGO LODGE
Flood cause: Heavy Rain / Tropical System
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Two feet of rock and debris covered Highway 62 near Valley View Rd, and small boulders were on the highway from Senilis Ave to east of Valley View Rd.

Flash Flood in INYO, CALIFORNIA
From 20-AUG-23 23:00:00 to 21-AUG-23 08:00:00 (PST-8)
Location: LONE PINE
Flood cause: Heavy Rain / Tropical System
Property damage: 10.00M
Crop damage: 0.00K
Reported by: Park/Forest Service

Fast flowing water, rock, and debris covered Whitney Portal Rd, the Whitney Portal parking lots, and the road to Lone Pine Campground. Whitney Portal Rd was destroyed by high flows in Lone Pine Creek.

Flood in SAN BERNARDINO, CALIFORNIA
From 21-AUG-23 06:32:00 to 21-AUG-23 12:00:00 (PST-8)
Location: HORSE THIEF SPGS
Flood cause: Heavy Rain / Tropical System
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Public

The Amargosa River flooded Old Spanish Trail Crossing in Tecopa for several hours.

Flash Flood in INYO, CALIFORNIA
From 20-AUG-23 18:47:00 to 20-AUG-23 20:30:00 (PST-8)
Location: CARTAGO
Flood cause: Heavy Rain / Tropical System
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Law Enforcement

A slide of mud and gravel covered Highway 395 at Ash Creek Rd. Mud flowed heavily along the side of the highway and into part of the southbound lanes. Due to ongoing flooding in multiple places, Highway 395 was eventually closed all the way from Bishop to Pearsonville overnight.