NASHVILLE, Tenn. >> A new layer of ice formed over parts of Tennessee on Thursday after a deadly storm blanketed the state in snow and sent temperatures plummeting earlier this week — part of a broader bout of bitter cold sweeping the country from Oregon to the Northeast.

Authorities said at least 14 deaths in Tennessee alone are blamed on the system, which dumped more than 9 inches (23 centimeters) of snow since Sunday on parts of Nashville, a city that rarely see such accumulations. Temperatures also plunged below zero (minus-18 Celsius) in parts of the state, creating the largest power demand ever across the seven states served by the Tennessee Valley Authority.

Thursday’s freezing rain compounded problems, adding a thin glaze of ice in some areas ahead of another expected plunge in temperatures over the weekend. Many schools and government offices have closed, and the state Legislature also shut down, canceling in-person meetings all week.

Near Portland, Oregon, ice slowly began to melt in areas south of the city as warmer temperatures and rain arrived Thursday. But a National Weather Service advisory through Friday warned of freezing rain and gusting winds of up to 40 mph (65 kph) for parts of the state. Most Portland-area school districts canceled classes for a third straight day because of slick roads and water damage from burst frozen pipes.

On Wednesday, a power line fell on a parked car in northeastern Portland, killing three people and injuring a baby during an ice storm that made driving in parts of the Pacific Northwest treacherous.

More than 40 deaths nationwide have been attributed to the frigid weather in the past week.

The dead in Tennessee included a box truck driver who slid into a tractor-trailer on an interstate, a man who fell through a skylight while cleaning a roof, and a woman who died of hypothermia after being found unresponsive in her home. The deaths occurred in nine Tennessee counties spanning more than 400 miles (640 kilometers).

The Tennessee Highway Patrol said it also investigated three fatal car wrecks caused by the storm, more than 200 wrecks involving injuries and more than 600 others without injuries.

Shelby County, which includes Memphis and is the state’s largest county, has had the most deaths, five. But officials have declined to release many details about the deaths, citing privacy concerns for the families involved. Tennessee’s Department of Health also refused to confirm accounts provided by local authorities of deaths likely tied to the 14-death total.

Across the country in Washington state, five people died from hypothermia over a four-day span that saw temperatures plummet to well below freezing in Seattle, the King County Medical Examiner’s office said.

Three of those who died between Jan. 11 and Jan. 15 were presumed homeless, said Kate Cole, a spokesperson for Public Health — Seattle and King County, in an email. One other person was temporarily housed, and one lived in a private residence. She cautioned that since reporting and investigating deaths takes time, the toll could still rise.

And in western New York, the icy weather was blamed for three deaths in three days. Then on Thursday, an American Airlines plane slid off a snowy taxiway in Rochester, New York, after a flight from Philadelphia. No injuries were reported.

Five people were struck and killed by a tractor-trailer on Interstate 81 in northeastern Pennsylvania after they left their vehicles following a separate crash on slick pavement.

In Kansas, authorities were investigating the death of an 18-year-old whose body was found Wednesday in a ditch not far from where his vehicle had become stuck in snow.

And in Mississippi, where officials reported five winter weather-related deaths, an estimated 12,000 customers in the capital city of Jackson were dealing with low water pressure Thursday. It was the latest setback for the city’s long-troubled water system.

Pipe breaks accelerated Wednesday when the frozen ground began to thaw and expand, putting pressure on buried pipes, Jackson water officials said.

Memphis’ power and water company, meanwhile, asked customers to avoid nonessential water use because of high demand and low pressure, citing leaks. Memphis, Light, Gas and Water said it had repaired 27 broken water mains since Saturday.

Joshua Phillips was walking his dog Thursday in Memphis as cars crawled by, skidding and sliding. He said he had shoveled snow off of his back patio and driveway but they were now covered in a thin coat of ice. Parts of the city saw nearly 5 inches of snow from the earlier storm.

Phillips said he helped a man push his car, which was stuck in the ice.

“What I’m more concerned about are the people who are unhoused and are outside in storms like this and don’t have any place to go,” he said.

In Nashville, Will Compton of the nonprofit Open Table Nashville, which helps homeless people, was canvassing downtown for people needing supplies or rides to warming centers or shelters.

On Thursday, he stopped his SUV outside the Country Music Hall of Fame and Museum to hand out warm hats, blankets, protein drinks and socks to some men standing outside as icy rain fell.

“People who are poor and people who are homeless are getting hit the hardest,” said Compton. He added: “A cold spell kind of predictably happens once a winter at least, and yet we’re still kind of caught scrambling and finding enough shelter beds for people.”

Aaron Robison, 62, has been staying at one of the city’s warming centers and said the cold wouldn’t have bothered him when he was younger. But now with arthritis in his hip and having to rely on two canes, he needed to get out of the cold.

“Thank God for people helping people on the streets. That’s a blessing,” he said.

Sainz reported from Memphis. Kimberlee Kruesi in Nashville, Michael Goldberg in Jackson, Mississippi, Rebecca Reynolds in Louisville, Kentucky, Heather Hollingsworth in Kansas City, David Caruso in New York, and Rebecca Boone in Boise, Idaho, contributed to this report.