201911.18
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Big weather change for Southern California: Rain, snow and possible flooding in the forecast

by in News

Southern Californians will see a big flip in the weather Tuesday, from record heat and red flag fire warnings to rain, thunderstorms, snow and cooler temperatures along with flash flood and winter storm watches over the next few days.

The most significant part of the system was forecast to hit Riverside and San Bernardino counties and inland Orange County. On Sunday, those areas were under a red flag warning for fire danger.

Less rainfall is forecast for Los Angeles County, and while snow levels will be at 6,000 feet, in amounts that “do not look that impressive,” the National Weather Service said.

Anticipated flash flood watch areas include the Temescal Valley around Lake Elsinore, where the Holy fire burned through; the San Jacinto Mountains in Riverside County, hit by the Cranston fire near Idyllwild and Mountain Center; and mountain and foothill areas in San Bernardino County, including the  Valley fire burn area near Forest Falls and Mountain Home Village. All of the fires struck in 2018

Caltrans said Monday areas of concern were Highway 38 in the Valley fire area; Highway 74 and the 15 Freeway for areas hit by the Holy Fire; and highways 74 and 243 in the Cranston fire footprint. Caltrans recently completed work on restoring a stretch of Highway 243 that was cratered by storm damage in February, and also spent months repairing Highway 74 as well, at a combined estimated cost of $21.5 million.

Winter storm watches will include mountain areas of Riverside and San Bernardino counties.

The flash flood watch is forecast from Tuesday evening through late Wednesday night, and the winter storm watch from Wednesday morning through Thursday evening.

A winter storm warning to the north includes Fort Tejon and Grapevine alongside the 5 Freeway in Kern County, the stretch that includes the Tejon Pass grade. It will be in effect from from early Wednesday to Thursday afternoon, the NWS said.

The Inland Southern California rains may bring “a potential threat to recent burn scars,”  the Riverside County Emergency Management Department tweeted Monday, adding that local public safety agencies  will monitor the system as it moves into the area.

“This is the time of year when we typically see dramatic changes” for California weather, National Weather Service meteorologist Alex Tardy said Monday from the agency’s San Diego office. He noted that even Monday afternoon, there were warm, dry Santa Ana winds.

“There’s been a big ridge of high pressure blocking the rain systems for California,” he said. But a low pressure system of cold air was moving in from north and will merge with a southerly system of moisture on Tuesday, bringing a rain and snow with a peak day of Wednesday.

“It will tap into a perfect recipe for rainfall, and rainfall that will be heavy at times,” Tardy said. Rainfall could total 1 to 2 inches, depending on where it falls.

“We have not seen any really significant rain since May, so there may be urban flooding problems and possible flash flooding,” he said. The heaviest part of the rain on Wednesday could also bring thunderstorms, he said.

Snow is forecast beginning at the 6,000-foot level for Riverside and San Bernardino county mountains, with ski-resort elevations perhaps getting as much as 4 to 8 inches of snow and lower elevations such as Big Bear City getting 1 to 3 inches, Tardy said.

Caltrans said its snowplows and crews were ready, and reminded drivers to avoid mountain driving during storms, that roads could get icy, and chains might be required for some roads.