Stranded in California’s Heavy Snow

Record snowfall and freezing temperatures have altered the landscape and lives of millions of people in California in recent weeks. The mountains behind the iconic Hollywood sign in Los Angeles are dusted in white. Yosemite National Park is closed to the public, and mountain roads are coated with black ice.

Vineyards in Napa Valley were dusted with powdery snow. Snow met the sand on a beach in Santa Cruz.

In the Greater Lake Tahoe area, which includes the city of South Lake Tahoe, a winter storm warning will be going into effect Saturday morning through Monday morning, the National Weather Service said. Heavy snow accumulations of 1 to 2 feet, and up to 4 feet in higher elevations, are expected still.

“If you come to the Sierra this weekend, you may not be able to leave for a while,” the Weather Service said.

In El Dorado County, which includes South Lake Tahoe, search and rescue crews and off-highway vehicle units were responding to calls from residents who needed evacuating from their homes, help with snow removal or rescue while stranded on roads, Sgt. Alexander W. Sorey, a spokesman for the sheriff’s department, said on Friday.

As steady snowfall fell in the mountains of Southern California last week, residents at lower elevations dealt with the fallout from a more familiar threat: too much water. Intense rains and powerful winds pounded Los Angeles and surrounding counties last week, producing significant flooding in urban areas.

But in Los Angeles, meteorologists reported a rare sight, when snow, or graupel — the soft, wet precipitation that is not quite as hard as hail — descended on the Hollywood sign.

The storms hitting the Yosemite area to the north have been coupled with freezing temperatures. This week, in one sign of the extreme weather, the floor of the Yosemite Valley had 40 inches of snow depth. The park was closed, and no date has been set for it to reopen.

Scott Gediman, a ranger and spokesman for the national park, said crews were digging out roads and trying to clear parking lots on Friday morning. The skies were clear, but the weather forecast called for 18 to 24 more inches of snow to come, from Saturday through Monday.

“It is just keeping on,” he said. “People are working hard. We are concerned about the storm coming in.”

In Madera County, Sheriff Tyson J. Pogue said crews had been evacuating or helping residents who had run out of food, water and fuel, particularly in Bass Lake and North Fork. Some had been taken to American Red Cross shelters.

“People have been snowed in to their homes,” he said. “A lot of those residents are trying to get propane trucks up and resupply for the next storm.”

Rescues were continuing farther south in the San Bernardino Mountains, where about 10 feet of snow had accumulated around the houses and roads, said David Wert, a county spokesman. About 80,000 people, many of them transient or seasonal renters, live in Big Bear Lake and smaller, unincorporated communities on the mountain.

“We doubt very much they came up there prepared,” Mr. Wert said.

Many people there also have run out of food, medicine, water and propane, he said. Some tried to flee the back-to-back storms but abandoned their vehicles on the impassable roads, which are narrow and winding, making it hard for snow plows to get around the buried cars. A unit of the office of emergency services is assisting with the rescues, he said.

“Everyone has been working around the clock to try to dig them out,” he said. “It is something no one here has ever seen.”