Heavy Rain, Flooding Expected Across Orange County-Trabuco Canyon

ORANGE COUNTY, CA - The Southland was targeted by yet another storm Wednesday, with light showers dousing the area in the morning ahead of heavier rainfall forecast for late Wednesday evening into Thursday, strengthened by an atmospheric river suffused with moisture. The National Weather Service shared a satellite image of that storm system, depicting a large area of low pressure bearing down on the state through the end of the week.

The strong storm cell traveled through Orange County Wednesday, dramatically increasing the amount of rainfall in the region. An inch-and-a-half or more of rain fell in parts of Fullerton, Yorba Linda, Anaheim Hills and two-inches of rain or more fell in Garden Grove, parts of Anaheim and Huntington Beach and 3.5 inches of rain was reported in Seal Beach, according to the NWS.

In a briefing early Wednesday afternoon, NWS officials said a flash flood watch will be in effect for "first-year burn areas" and the following conditions were expected through Thursday:

• high surf and significant coastal flooding;
• rain totals of 1-3 inches along the coasts and valleys, with 2-4 inches in the foothills and mountains;
• snow accumulations at the highest resort levels above 8,000 feet
• shallow mud and debris flows with some damage possible.

Scattered showers increased in intensity all day Wednesday, increasing in severity overnight, according to National Weather Service meteorologist Kathy Hoxsie. The atmospheric river, which Hoxsie described as a moisture-packing air mass is pushing the the storm which she said has "more moisture than the others."

In Orange County, scattered light showers Wednesday promised to give way to heavier rainfall arriving late evening, NWS meteorologist Jimmy Taeger said. Thursday will bring the heaviest rain before giving way to drier conditions on Friday.

A flash flood watch remains in effect through Thursday afternoon, according to the NWS. Laguna Beach and other coastal communities advised homes and businesses to "put up their flood gates" overnight and sand bag where needed to divert water flow.

Flooding impacted a mobile home park in Huntington Beach, with water rising to the doorways of some homes. Pacific Coast Highway was closed in both directions between Warner Avenue and Seapoint Street, and Huntington Beach police said the stretch will likely remain blocked into Thursday due to the additional rain coming through Wednesday.

Sand bags were made available to all residents of coastal communities as well as cities across the county, at Orange County Fire Authority stations and most city public works yards.

As the rain continues today, HB residents can obtain sandbags at the City Corporate Yard and the Warner Fire Station located at Warner and PCH. The HBFD asks drivers to slow their speed due to the wet conditions and potential flooding. #Huntingtonbeach pic.twitter.com/WZOApCpdBC
— Huntington Beach FD (@HBFD_PIO) January" class="redactor-linkify-object">https://twitter.com/HBFD_PIO/s... 16, 2019

Between 1.5 to 2 inches of rain was forecast for the Malibu area, enough to cause mud or debris flows, Hoxsie said. The rain, however, is expected to fall over a longer period of time Wednesday, slightly reducing the chances of mud or debris flows, she said.

Several parts of Malibu impacted by November's Woolsey Fire, which stripped many hillsides bare, are already under mandatory evacuation orders.

Updated rainfall forecast through Thursday night / Widespread rain expected to begin late this afternoon and continue through Thursday evening / Street flooding is likely / Use caution while driving and avoid flooded roads #cawx pic.twitter.com/DH1b14klHG
— NWS San Diego (@NWSSanDiego) January" class="redactor-linkify-object">https://twitter.com/NWSSanDieg... 16, 2019

National Weather Service Photo