By 4:20 p.m. (7:20 p.m. ET) the weather service estimated that “widespread rain” across the Los Angeles Basin would affect the Monday evening commute. “Be prepared for potential road closures and travel delays due to flooding, debris flows, and mud/rock slides,” the service said in its tweet. Santa Barbara County, Ventura County and Los Angeles county are affected. By Monday afternoon, mandatory evacuations were also underway in parts of Los Angles County. Expected heavy rainfall could trigger mudslides in burn-scar areas.
Thomas fire, the largest wildfire in California history, was about 92 percent contained as of Monday night. It has burned more than 440 square miles. Burn scars are especially susceptible to mudslides because wildfires can burn away all vegetation that holds back the land, leaving no defense against heavy rain. Higher rainfall totals, generally 3 to 5 inches, are possible on the southward-facing slopes in Southern California, including the Thomas Fire burn area. And it’s not all: snow totals of more than 6 inches are anticipated in elevations above 5,500 feet in Southern California.