LOS ANGELES (CBSLA.com) — A powerful Pacific storm is expected to unleash more downpours across the Southland Monday amid fierce winds that could trigger thunderstorms.

According to the National Weather Service, a flash flood watch will remain in effect until 6 p.m. in Los Angeles County.

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A SigAlert remained in effect in both directions of Malibu Canyon Road from Francisco Ranch Road to Piuma Road in Malibu due to rock slides.

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Topanga Canyon Boulevard was also shut down from Pacific Coast Highway to Grand View Drive.

Dangerous conditions characterized by waves of up to 18 feet were reported in the Pacific Ocean Sunday while heavy snow accumulation occurred in the San Gabriel Mountains.

Along the coast, beach erosion, dangerous rip currents, and sneaker waves posed a threat to beachgoers.

Windy conditions were reported in the Antelope Valley.

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