Powerful storm batters California with dangerous flooding

Some 37 million people are on alert for flooding from Sacramento in Northern California to San Diego in Southern California.

The Santa Barbara Airport closed Monday morning due to flooding. More than 2.5 inches of rain fell in Santa Barbara before dawn and more is expected.

Flash flooding, mud and debris flows, as well as landslides and rockslides, are likely.

Flash flood threat.

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Severe storms could hit the Sacramento region on Monday with a risk of brief tornadoes, damaging winds, large amounts of small hail, lightning and heavy rainfall rates. The greatest threat for storms in this area comes between noon and 8 p.m. PT.

Areas north of San Francisco reported 2 to 4 inches of rain from the weekend, and now there’s a slight risk for excessive rainfall from Los Angeles to the San Francisco Bay area to Sacramento on Monday.

Flood threat Monday to Wednesday.

Much of the areas under flood watches are also on alert for high winds. Gusts could reach 40 to 60 mph on Monday, especially in the morning.

High surf advisories are in effect from San Francisco to San Diego. Large breaking waves from 18 to 28 feet are possible through Tuesday. Coastal flooding is also possible, especially during high tide.

Total rainfall amounts of 2 to 5 inches are expected over the lower elevations, with 4 to 8 inches over the foothills and mountains with local amounts to 10 inches.

Rainfall rates of 1 inch per hour are possible.

Downtown Los Angeles only needs 3 inches of rain to have the rainiest February on record.

Storm timing for Tuesday.

In the mountains, 2 to 5 feet of snow is generally expected in higher elevations of the Sierra Nevada, along with gusty winds making travel impossible at times.

In the San Bernardino Mountains, up to 8 inches of snow is possible, with accumulation beginning Monday night and ending Wednesday morning.

The storm system is forecast to continue impacting California through Tuesday before it moves out of the region on Wednesday.