A strong trough and associated Pacific cold front swept into Southern California from the west, bringing strong winds, heavy snow and rain. The storm was noteworthy for the strong prefrontal southerly winds that produced significant tree damage over the coast and valleys. In the mountains the ski resorts received 1-2 ft of snow, while elevations as low as 5,000 ft saw a few inches of accumulation. Rainfall ranged from 2-6 inches along the coastal slopes to 1-2 inches at the coast. At the beaches surf heights reached 8 to 12 ft. Damages, primarily from wind, reached into the millions of dollars.

High Surf in ORANGE COUNTY COASTAL, CALIFORNIA
From 17-FEB-17 16:00:00 to 19-FEB-17 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Lifeguard

Lifeguards reported sets of 8-12 ft at Laguna Beach and 10-15 ft at San Clemente Beach. Sets near 10 ft were also reported in Newport Beach.

Thunderstorm Wind in ORANGE, CALIFORNIA
From 17-FEB-17 17:30:00 to 17-FEB-17 18:00:00 (PST-8)
Location: LAGUNA BEACH
Magnitude: 58.00 MG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Mesonet

Roughly 20 trees were downed by convective winds in Laguna Beach. The nearby Laguna Beach mesonet station measured a peak gust of 67 mph at 1737PST.

Flood in SAN BERNARDINO, CALIFORNIA
From 17-FEB-17 17:40:00 to 17-FEB-17 18:40:00 (PST-8)
Location: PHELAN
Flood cause: Heavy Rain
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Law Enforcement

A jeep was submerged in a large sink hole at the intersection of Cedar St. and Chateau Rd. No water rescues required.

Flash Flood in ORANGE, CALIFORNIA
From 17-FEB-17 18:00:00 to 17-FEB-17 20:00:00 (PST-8)
Location: SANTA ANA GARDENS
Flood cause: Heavy Rain
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Flood waters from the Wintersburg Channel exceeded the channels banks, producing flooding in a mobile home park.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 17-FEB-17 16:50:00 to 17-FEB-17 18:00:00 (PST-8)
Location: SUMMIT
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported water across all lanes of Highway 138 near Summit Valley Rd.

Debris Flow in SAN BERNARDINO, CALIFORNIA
From 17-FEB-17 16:00:00 to 17-FEB-17 18:00:00 (PST-8)
Location: CAJON
Flood cause: Heavy Rain
Property damage: 500.00K
Crop damage: 0.00K
Reported by: Broadcast Media

A big rig and car were caught in a mud flow near Highway 138 and Lone Pine Rd. Elsewhere along Highway 138 mud flows caused significant damage to area roadways.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 17-FEB-17 17:40:00 to 17-FEB-17 18:20:00 (PST-8)
Location: VICTORVILLE
Flood cause: Heavy Rain
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Three vehicles swept from Rodeo Dr. near Pebble Beach Park. Swift water rescues were conducted to rescue 3 people. One fatality was reported.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 17-FEB-17 19:45:00 to 18-FEB-17 02:45:00 (PST-8)
Location: CAJON
Flood cause: Heavy Rain
Property damage: 3.50M
Crop damage: 0.00K
Reported by: Trained Spotter

Flood waters and related erosion caused a collapse of lane number 5 along Interstate 15. A fire truck and big rig were caught up and destroyed in the collapse. No injuries were reported but damages to the Interstate reached into the millions.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 18-FEB-17 00:20:00 to 18-FEB-17 01:10:00 (PST-8)
Location: KEENBROOK
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Flood waters in the Cajon Pass submerged a vehicle along Keenbrook Rd. Three swift water rescues were conduced with no injuries reported.

High Wind in ORANGE COUNTY COASTAL, CALIFORNIA
From 17-FEB-17 13:00:00 to 17-FEB-17 19:00:00 (PST-8)
Magnitude: 52.00 MG
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet stations along the coast reported wind gusts in the 30 to 45 mph range over a 6 hour period between 1300 and 1900PST. An isolated peak gust of 60 mph occurred at San Clemente Pier. Numerous trees were downed over the coastal areas.

High Wind in SAN DIEGO COUNTY MOUNTAINS, CALIFORNIA
From 17-FEB-17 14:00:00 to 17-FEB-17 20:00:00 (PST-8)
Magnitude: 65.00 MG
Reported by: Mesonet

Numerous 70 mph or higher wind gusts were reported by the Palomar Mt. mesonet station over a 6 hour period. Peak gusts to 75 mph occurred between 1820 and 1830PST. No damage reports were received for the mountains areas.

High Wind in SAN BERNARDINO COUNTY MOUNTAINS, CALIFORNIA
From 17-FEB-17 07:30:00 to 17-FEB-17 18:00:00 (PST-8)
Magnitude: 73.00 MG
Reported by: Mesonet

The Burns Canyon mesonet reported frequent 70 to 80 mph gusts over a 9 hour period, with a peak gust of 84 mph between 1151 and 1251PST. A gust to 71 mph also occurred at Heaps Peak near Running Springs between 1015 and 1115PST. No damage reports were received.

High Wind in APPLE AND LUCERNE VALLEYS, CALIFORNIA
From 17-FEB-17 10:00:00 to 17-FEB-17 19:00:00 (PST-8)
Magnitude: 63.00 MG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Mesonet

Frequent wind gusts in the 55-65 mph range were measured by mesonet stations in Hesperia, with a peak gust of 72 mph between 1410 and 1420PST. Big rigs were blown over along Interstate 15 below the Cajon Pass and along Phelan Rd. west of Hesperia.

Heavy Snow in SAN BERNARDINO COUNTY MOUNTAINS, CALIFORNIA
From 17-FEB-17 14:00:00 to 18-FEB-17 03:00:00 (PST-8)
Reported by: Public

Thirteen hour snow totals ranged from 12-24 inches above 6,500 ft, to a trace as low as 4,500 ft. Mt. Baldy and Mountain High ski resorts reported 16 to 24 inches of snow over a 13 hour period, while Green Valley Lake received 12 inches. Other snow totals included 8 inches in Wrightwood, 6 inches in Running Springs, and 3 inches in Big Bear.

High Wind in SAN DIEGO COUNTY COASTAL AREAS, CALIFORNIA
From 17-FEB-17 10:00:00 to 17-FEB-17 19:00:00 (PST-8)
Magnitude: 53.00 MG
Property damage: 7.00M
Crop damage: 100.00K
Reported by: County Official

Strong southerly winds downed hundreds of trees across coastal San Diego County. Many Cars were crushed by falling trees, power lines were downed, homes and business were damaged and one fatality was reported in East San Diego. The San Diego metro was hardest hit, with several mesonet/ASOS sites reporting wind gusts in the 50 to 60 mph range. A peak gust of 61 mph occurred at Imperial Beach. Storm damages reached the millions of dollars.

High Wind in SAN DIEGO COUNTY VALLEYS, CALIFORNIA
From 17-FEB-17 11:00:00 to 17-FEB-17 20:00:00 (PST-8)
Magnitude: 50.00 MG
Property damage: 2.00M
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous trees were downed across the western valleys of San Diego County. Peak wind gusts generally ranged between 35 and 50 mph, though a peak gust of 58 mph was reported at Otay Mountain between 1414 and 1514PST.

Strong Wind in ORANGE COUNTY INLAND, CALIFORNIA
From 17-FEB-17 13:00:00 to 17-FEB-17 19:00:00 (PST-8)
Magnitude: 39.00 EG
Property damage: 200.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet stations across inland Orange County reported wind gusts of 30 to 45 mph over a 6 hour period between 1300 and 1900PST.  Numerous trees and a few power lines were downed in Santa Ana and Tustin. The falling trees smashed cars blocked roadways.

High Surf in SAN DIEGO COUNTY COASTAL AREAS, CALIFORNIA
From 17-FEB-17 13:00:00 to 18-FEB-17 21:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Lifeguard

Multiple lifeguard reports of high surf along the San Diego County coast. Oceanside Beach reported 8-12 ft surf with peak sets near 16 ft on the afternoon of the 18th. Imperial Beach reported sets to 8 ft. Average sets of 7 ft were reported at Mission Beach and Solana Beach.