LOS ANGELES (CNS) - A storm suffused with moisture from an atmospheric river rolled into the Southland today, triggering widespread rainfall, strong winds and warnings of flash flooding.
A flash flood watch issued by the National Weather Service will be in effect from 7 a.m. to 3 p.m. in the Getty, Saddleridge and Tick burn areas in L.A. County.
“Moderate to heavy rainfall is expected near recent burn areas from a cold and vigorous storm system,” the weather service said in a statement. “Rainfall rates between 0.50 inch per hour and 1 inch per hour are possible, especially near thunderstorms. The recent burn areas in Los Angeles County will be especiall at risk for flash flooding and mud and debris flows due to moderate to heavy rainfall. Road closures and property damage may occur due to mud and debris flows.”
In Orange County, a flash flood watch will be in force from 6 this morning through this afternoon.
“Areas most at risk include low-lying intersections, areas with poor drainage, and the coastal mountain slopes, where the rainfall will be the greatest,” warned the San Diego office of the NWS, which monitors conditions in Orange County. “Mud slides and debris flows are possible in and below recently burned areas.”
Meteorologist David Sweet at the Oxnard office of the National Weather Service said the atmospheric river -- a long, narrow plum of moisture in the atmosphere -- is drawing its moisture from near Hawaii. Atmospheric rivers “can produce heavy rainfa;;,” he said.
The NWS forecast between three-quarters of an inch of rain and an inch- and-a-half in the region but between an inch-and-a-half and three inches in the eastern San Gabriels.
The snow level, meanwhile, will remain high -- at the 7,000-foot level.
Forecasters said a moist and unstable air mass will bring the potential for thunderstorms to coastal waters.
“Any thunderstorm that forms will be capable of producing locally gale force winds and rough seas, dangerous lightning, heavy rainfall with reduced visibility, small hail, and waterspouts. If a thunderstorm develops, mariners should consider seeking safe shelter in a nearby harbor,” urged an NWS statement.
In the San Gabriel Mountains in L.A. County, a wind advisory will be in effect until 3 p.m.
Forecasters said southeast winds of 20 to 35 mph with gusts of between 45 and 50 mph would buffet the San Gabriels.
“Gusty winds will make driving difficult and could blow around unsecured objects. Tree limbs could be blown down and a few power outages may result,” warned an NWS statement. “Use extra caution when driving, especially if operating a high-profile vehicle. Secure outdoor objects.”
The NWS forecast rain in L.A County today and highs of 45 degrees on Mount Wilson; 50 in Lancaster; 51 in Palmdale; 54 in Saugus; 58 in Pasadena, Burbank and Woodland Hills; 59 in San Gabriel; 60 in Avalon; and 61 in Downtown L.A., Long Beach and at LAX. Similar temperatures were forecast for several days, including amid rain on Saturday, but a warming trend will get underway Monday.
The NWS forecast showers in Orange Coounty today and highs of 47 degrees on Santiago Peak; 53 on Ortega Highway at 2,600 feet; 58 at Fremont Canyon and Trabuco Canyon; 60 in Yorba Linda; 61 in Mission Viejo; 62 in Laguna Beach, San Clemente and Anaheim; 63 in Newport Beach; and 64 in Fullerton and Irvine. Temperatures will be roughly the same for several days, including amid rain on Saturday.