As a new cold low pressure system headed for Southern California this morning, flooding developed on an L.A. area freeway early today and the National Weather Service issued a flash flood warning for Orange County.
During the night, the California Highway Patrol issued a SigAlert for the northbound Harbor (110) Freeway from Redondo Beach Boulevard to the Glen Anderson (105) Freeway and for the southbound Harbor Freeway from the Glen Anderson Freeway to Redondo Beach Boulevard in Gardena due to flooding over all lanes except the express lanes. Some lanes were later re-opened.
Additionally, the National Weather Service issued a flash flood warning effective until 7:30 a.m. for the Silverado burn area in Orange county, saying heavy rainfall and isolated thunderstorms were moving into the area.
“Rainfall exceeding a half-inch or more in one hour could cause flash flooding and mud and debris flows,” an NWS statement said, adding that the flooding was mainly expected over mostly rural areas of east central Orange County.
Also expected, as a result of the new cold low-pressure system sliding into Southern California, are more snow showers in the mountains of Santa Barbara, Ventura and Los Angeles counties, though not the Santa Monica range. The snow showers in the San Gabriel Mountains are expected through the evening.
A winter weather advisory denoting hazardous travel conditions — including snowfall, small hail as a result of isolated thunderstorms, and poor visibility — was scheduled to be in effect in the San Gabriels until 6 p.m.
Three to six inches of snow are expected above 5,000 feet, and one to three inches are forecast between 4,000 and 5,000 feet, NWS forecasters said.
Snow “showers will become widespread around noon, then continue through this evening,” according to an NWS statement, which said the snow likely would affect travel on the Angeles Crest Highway, portions of Interstate 5 near The Grapevine, and state Route 33 in Ventura County. Chains may be necessary on those roads.
Temperatures today will be in the high 50s and low 60s. Showers are forecast in non-mountain communities today, giving way to partly cloudy skies Tuesday and sunshine for several days beginning Wednesday.