Deadly bomb cyclone batters Northwest, causing widespread power outages and downing trees

A major storm battered the U.S. Northwest with strong winds and rain, causing widespread power outages, closing schools and downing trees that killed at least two people.

The Weather Prediction Center issued excessive rainfall risks through Friday, and hurricane-force wind warnings were in effect as the strongest atmospheric river — a large plume of moisture — that California and the Pacific Northwest has seen this season overwhelmed the region. The storm system, which hit starting Tuesday, is considered a "bomb cyclone," which occurs when a cyclone intensifies rapidly.

The intensity of the atmospheric river was expected to peak on Thursday, although forecasters warned that another bout of severe weather was yet to come.

A second storm system still developing off the West Coast was forecast to bring more wind to the Pacific Northwest on Friday and proceed to push heavy snow toward the northern Rocky Mountains, the Weather Prediction Center said. "Impactful and for some places dangerous weather conditions will continue through early this weekend as two separate storm systems impact the Lower 48," the center wrote in an advisory.

Social media video showed the beginning of snowfall early Thursday in Ohio, as CBS News meteorologist Nikki Nolan reported that snow was expected to move into the Great Lakes region.

In California, the National Weather Service extended a flood watch into Saturday for areas north of San Francisco. Up to 16 inches of rain was forecast in Northern California and southwestern Oregon through Friday. Dangerous flash flooding, rock slides and debris flows were possible, officials warned.

A winter storm watch was in place for the northern Sierra Nevada above 3,500 feet, where 15 inches of snow was possible over two days. Wind gusts could top 75 mph in mountain areas, forecasters said.

Heavy, wet snow was expected to continue along the Cascades and in parts of far Northern California. Forecasters warned of blizzard and whiteout conditions and near impossible travel at pass level due to accumulation rates of 2 to 3 inches per hour and wind gusts of up to 65 mph.

Falling trees struck homes and littered roads across northwest Washington. In Lynnwood, Washington, a woman died Tuesday night when a large tree fell on a homeless encampment, South County Fire said in a statement on social media. Another woman died Tuesday in Bellevue, Washington, about 20 miles from Lynwood, according to the Bellevue Fire Department. 

Fire officials and medics responded to a 911 call around 7 p.m. Tuesday, where a man reported that a falling tree collapsed into his home and struck his wife, who was in the shower, the fire department said in a Facebook post. The woman was confirmed dead by medics when they arrived at the scene.

"She was in the shower at the time when the tree fell," Bellevue Fire Department spokesperson Heather Wong told CBS News.

However, firefighters had been unable to remove the tree to reach her.

"We're doing the absolute best that we can," Wong said. "It's looking like we might have to get a crane out to lift the tree up."

In Seattle, a tree fell onto a vehicle, temporarily trapping someone inside, the Seattle Fire Department reported. The agency later said the person was in stable condition.

"Trees are coming down all over the city & falling onto homes," Bellevue Fire said in another social media post. "If you can, go to the lowest floor and stay away from windows. Do not go outside if you can avoid it."

A fire department in Washington state posted images on X of some of the damage its personnel encountered early Wednesday: 

Tracy Meloy of Issaquah, Washington, felt well-prepared for the storm Tuesday afternoon, with dinner prepped and lanterns ready. But then she spent the night listening to wind-whipped debris hit the outside of her home, including a particularly loud "thump" around 9 p.m. The next morning morning she ventured outside to survey the damage to her neighborhood, about 17 miles east of Seattle.

"Now that I'm standing here in front of the house, I can tell it's the tree that was across the street," Meloy said. The tree pulled down the power lines in front of her home, and limbs, leaves and other plants were strewn all over the road.

"It looks like a forest floor instead of a street," she said.

The number of power outage reports in Washington fluctuated wildly Tuesday night but steadily declined to about 330,000 by Thursday morning, according to utility tracker PowerOutage.us. More than a dozen schools have closed this week in Seattle alone, and the U.S. Coast Guard announced Wednesday night that river bar crossings to the ocean would be closed to traffic from Quillayute River in Washington to Humboldt Bay in California.

 Early Wednesday morning, Puget Sound Energy said in a statement that its nearly half-million customers without power should expect a "multiple day outage," CBS' Seattle affiliate KIRO-TV reported.

About 2,100 customers were reported to be without power Wednesday evening in Oregon and 20,000 in California. In Reno, Nevada, three schools were closed, and semi-trucks were prohibited on the main highway between Carson City and Reno due to high winds. All chairlifts were shut down at the Mt. Rose Ski Resort near Lake Tahoe.

The weather service warned people on the West Coast about the danger of trees during high winds, posting on the social platform X: "Stay safe by avoiding exterior rooms and windows and by using caution when driving."

Southbound Interstate 5 was closed for an 11-mile stretch from Ashland, Oregon, to the California border on Wednesday morning due to extreme winter weather conditions in northern California, according to the Oregon Department of Transportation. It was expected to be a long-term closure, the department said.

The weather service issued a flood watch for parts of southwestern Oregon through Friday evening, while rough winds and seas halted a ferry route in northwestern Washington between Port Townsend and Coupeville for part of the day.

As Robert and Lisa Haynes of Issaquah surveyed the damage in their neighborhood, they saw fallen branches or trees blocking driveways and roads. They were stuck at home.

"It's like a snow day," Robert Haynes said, "but with no snow."

In Juneau, Alaska, gusts of wind up to 60 mph were forecast.

To the east, the first significant snow of the season in the Dakotas and Minnesota led to accidents and slippery roadways. The weather service said up to 16 inches could fall in the Turtle Mountains of North Dakota, and Minot could get up to 8 inches.

Officials advised people not no travel throughout northern North Dakota, and state troopers in northern Minnesota responded to several accidents including tractor-trailers that jackknifed on Interstate 94 after the roadway became slippery from snow and ice.

Winds were expected to be problematic in parts of Montana and Nebraska, with gusts up to 60 mph, the weather service said.

In:
• Atmospheric River
• Bomb Cyclone