PHELAN (CBSLA) – A powerful storm dumped several inches of snow in the San Gabriel and San Bernardino Mountains above Los Angeles Monday evening through Tuesday morning, forcing the closure of several schools and leaving drivers facing whiteout conditions.

A snowstorm near Wrightwood, Calif. March 11, 2019. (CBS2)

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Anywhere from 12 to 18 inches of snow were expected to fall in elevations above 5,000 feet, according to the National Weather Service. A winter storm warning was in effect through noon Tuesday.

The communities of Wrightwood, Big Bear and Running Springs were all seeing heavy snow.

“Significant blowing and drifting snow will be possible due to gusty north-northeast winds in the mountains,” the NWS said in a statement. “Use extreme caution if heading into the mountains, allow extra travel time, and have a winter survival kit.”

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In response the Bear Valley Unified School District closed all its schools, including: Big Bear Elementary, North Shore Elementary, Baldwin Lane Elementary, Big Bear Middle and High schools and Chautauqua High School.

While conditions were slippery, mountain highways were still open. Drivers hitting the Angeles Crest Highway, Big Pines Highway and Mt. Baldy Road were advised to be prepared for “significant reductions in visibility at times.”

As of 6 a.m., the Mountain High Resort near Wrightwood had reported 16 inches of snow over the past 24 hours.

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The snowfall was expected to taper off by Tuesday afternoon.