A massive storm system spanning from Northern California to Southern California has put 37 million people on alert for potential flooding. The Santa Barbara Airport was forced to close on Monday morning due to flooding caused by over 2.5 inches of rain. Flash flooding, mudslides, landslides, and rockslides are expected throughout the state. Severe storms are anticipated in the Sacramento region on Monday, with risks of brief tornadoes, damaging winds, hail, lightning, and heavy rainfall between noon and 8 p.m. PT.

Areas north of San Francisco have already reported 2 to 4 inches of rain over the weekend, with a possibility of excessive rainfall on Monday from Los Angeles to the San Francisco Bay area and up to Sacramento. Flood watches are in place, and high winds with gusts up to 40 to 60 mph are expected, especially in the morning. High surf advisories from San Francisco to San Diego warn of large breaking waves reaching 18 to 28 feet through Tuesday, potentially causing coastal flooding during high tide.

Rainfall amounts ranging from 2 to 5 inches are predicted over lower elevations, with up to 10 inches in some areas, while the Sierra Nevada mountains are set to receive 2 to 5 feet of snow. In the San Bernardino Mountains, snow accumulation of up to 8 inches is possible, starting Monday night and ending Wednesday morning. Downtown Los Angeles is close to breaking its rainiest February record with just 3 more inches needed. The storm system is forecast to persist in California through Tuesday before moving out of the region on Wednesday.