A late-February blast of arctic air produced a rare blizzard east of Los Angeles in the San Bernardino Mountains, where thousands of people live at high elevations in forest communities or visit for year-round recreation.

Extraordinary snowfall buried homes and businesses, overwhelming the capability of snowplowing equipment geared toward ordinary storms.

By last weekend, all highways leading up into the mountains were closed and have opened intermittently since then to residents and convoys of trucks loaded with food or other supplies.

The estimate by San Bernardino County Sheriff Shannon Dicus was an improvement in the outlook for stranded residents, which previously ranged up to two weeks.

“We’ve said we could push it out as far as two weeks but because of the state’s efforts and the equipment that’s coming in behind us we’re hoping to drop that down to a week,” he told a press conference.

The sheriff and other officials said progress has been made, but they described severe conditions that, for example, have forced firefighters to reach emergency scenes such as fires in snowcats.

“The enormity of this event is hard to comprehend,” said state Assemblyman Tom Lackey. “You know, we’re thinking, ‘We’re in Southern California,’ but yet we have had an inundation that has really, really generated a severe amount of anxiety, frustration and difficulty, especially to the victims and those who are actually trapped in their own home.”

San Bernardino County is one of 13 counties where California Gov. Gavin Newsom declared states of emergency due to the impacts of severe weather, including massive snowfalls that have collapsed roofs due to too much weight.

In the northern part of the state, mountain communities grappling with the conditions have smaller populations and are more accustomed to significant snowfall.

Residents and vacationers trapped in the San Bernardino range have taken to social media to show their plight and wonder when plows are coming.

Shelah Riggs said the street she lives on in Crestline hasn’t seen a snowplow in eight days, leaving people in about 80 homes along the roadway with nowhere to go. Typically, a plow comes every day or two when it snows, she said.

“We are covered with five or six feet (1.5 or 1.8 meters); nobody can get out of their driveways at all,” she said in a telephone interview.

Riggs, who lives with her 14-year-old daughter, said everyone is working to keep snow and ice off their decks to prevent collapse and making sure the gas vents on their homes are kept clear.

She said the county’s response has been “horrible” and that “people are really angry.”

Devine Horvath, also of Crestline, said it took her and her son 30 minutes to walk down the street to check on a neighbor — a trek that normally takes just a few minutes.

Horvath said she was lucky to make it to the local grocery store before its roof collapsed several days earlier but hadn’t been able to leave her street since.

“I’m getting more upset by the day,” she said.

The sheriff sought to give reassurance that help is coming even if people haven’t seen any plows.

“We’re going to dig you out and we are coming,” Dicus said. “We are making tremendous progress. I saw this from the air yesterday. The roads are being cleared.”

Officials said crews were dealing with such tremendous depths of snow that removal required front-end loaders and dump trucks rather than regular plows.

California Department of Transportation official Jim Rogers said crews working 24-hour shifts have removed more than 2.6 million cubic yards (1.9 million cubic meters) of snow from state highways.

Officials described a host of difficulties in reopening smaller roads, including buried vehicles and downed power lines that make progress difficult. Residents were urged to somehow mark the locations of cars.

A reopened road may only be the width of a single vehicle with walls of ice on each side.

“We are going house to house, and we’re literally using shovels to shovel out driveways to make sure that people have access to their cars,” said county fire Chief Dan Munsey. “As the roads are plowed, you still have a 10-foot (3-meter) berm of snow that you need to make it over.”

More snowcats were being brought in, along with a California National Guard crew that normally works with the California Wildfire & Forest Resilience Task Force on wildfires. The crew will help shovel snow.

While more heavy snow was forecast to arrive in Northern California early Saturday, Southern California was expected to remain storm-free except for possible light rain.

“The weather looks great for the next seven days, and that’s great news,” Munsey said.

About 80,000 people live in the San Bernardino Mountains either part or full time. The county has not estimated how many people are currently in the mountains because many residences are vacation homes or rentals.