SAN FRANCISCO (CBS SF) — Waves of frigid air continued to cascade down the West Coast Tuesday, plunging temperatures to near freezing levels across the San Francisco Bay Area, triggering snow flurries in the hills above Wine Country and keeping I-80 shutdown in the snowbound Sierra.

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Another round of isolated showers dampened Bay Area roadways during the Tuesday morning commute with heavier rain predicted for Tuesday evening into Wednesday morning.

“There will be more noticeable rain Tuesday night through Wednesday morning,” said KPIX 5 meteorologist Darrin Peck. “It’s not a lot, maybe a quarter inch of rain, and that’s it for Tuesday and Wednesday.”

Temperatures plunged into the mid-30 in some areas overnight, forcing residents in the Wine Country community of Angwin to scrape off snow and frost from their windshields.

 

“As a general rule of thumb, there’s 50% chance of seeing snow flakes they are below the freezing level,” the National Weather Service said. “Don’t expect accumulations of snow below 2000 ft. However the flakes can be fun to look at. They won’t last long, as warmer air moves in later this morning.”

A blanket of snow remained on Mt. Hamilton and Mt. Diablo.

 

Like communities across the Bay Area, the frigid conditions forced Marin County officials to activate their severe weather emergency shelter program for homeless people.

“We know that folks have been living through a number of wet days already, so we’re eager to get people indoors to dry off and warm up, especially those who are most medically needy,” Gary Naja-Riese, director of the county’s homelessness division, told the Marin Independent Journal.’

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Meanwhile in the snowbound Sierra, Highway 50 finally reopened to westbound and eastbound traffic from Placerville to Meyers early Tuesday.

I-80 remained closed from Colfax to the Nevada State-line as Caltrans crews worked around the clock to remove several feet of snow and fallen trees from the roadway.

At Donner Pass, officials with the University of California, Berkeley’s Central Sierra Snow Laboratory got another 8.4 inches over the last 24 hours bringing December’s total to 202 inches — the third snowiest month on record dating back to 1970.

“A spot of sunlight peaked through the clouds this morning,” lab workers tweeted. “But it won’t last long with more snow on the way.”

The National Weather Service echoed the prediction.

“Lighter accumulations (Tuesday morning) compared to recent days, but the next upper level feature diving through the West Coast will usher in yet another round of heavy snow to the Sierra Nevada late Tuesday into Wednesday,” forecasters warned. “By early Thursday morning, another 1 to 2 feet of snow will have fallen in throughout much of the Sierra Nevada with locally higher totals in the tallest peaks.”

The challenging weather conditions were slowing the search for 43-year-old Rory Angelotta, of Truckee, who has been missing ever since he was last seen Saturday morning at the Northstar ski resort.

According to the Placer County Sheriff’s Office, Angelotta was reported missing when he failed to show up for dinner Saturday night with friends. His car was found in the resort parking lot and his calls went straight to voicemail.

The Placer County Sheriff’s Office responded and immediately dispatched additional emergency resources including Tahoe Nordic Search and Rescue, Nevada County Search and Rescue and Northstar Ski Patrol on Sunday.

The investigation has revealed that around 11:30 a.m., Angelotta’s ski pass was scanned at the Comstock lift. There was no other activity registered to his pass since that time.

“Searchers responded and combed the mountain and surrounding areas, despite extreme weather,” the Placer County Sheriff’s Department said. “Rescue personnel were on skis, snowmobiles, and a snowcat during their search. They faced high avalanche danger, strong winds, whiteout flurries, frigid temperatures, and heavy snow loads before calling off their search in the evening.”

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The sheriff said Angelotta was an experienced skier and was believed to have avalanche equipment on him.