WASHINGTON — Rescuers sifted through rubble looking for more dead and wounded after two back-to-back tornadoes touched down in Alabama, killing at least 23 people, authorities said.

The storms inflicted their worst damage on Lee County, Alabama Sunday, an area that includes the state’s largest city of Auburn, destroying numerous homes and businesses.

More than 50 people were reported injured and the death toll is expected to rise.

Meanwhile, about 10 inches of snow was expected to fall in the New York City area by Monday morning with the arrival of another arctic blast, prompting all schools in the city to be closed and New Jersey to declare a state of emergency.

Punishing cold winds will make it feel 15 degrees below zero Fahrenheit in Chicago Monday with the wind-chill effect, the National Weather Service said. Actual temperatures will hover around 15 degrees Fahrenheit Monday.

Classes in schools across Boston were also cancelled or delayed as about 7 inches will fall by morning before turning into icy sleet, said Bob Oravec, a forecaster with the weather service.

“Winter is definitely not over,” Oravec said.

In Alabama, Lee County Sheriff Jay Jones said that rescue and recovery operations overnight were difficult.

“The challenge is the sheer volume of the debris where all the homes were located,” Jones said in an interview with CNN on Sunday. “The devastation is incredible,” he said.

“I cannot recall at least in the last 50 years... a situation where we have had this loss of life that we experienced today.”

On Twitter, US President Donald Trump urged residents of Alabama and other areas affected by the storms to be “careful and safe.” “Tornadoes and storms were truly violent and more could be coming,” Trump wrote. “To the families and friends of the victims, and to the injured, God bless you all!”

As thousands faced a night without power, temperatures in Alabama looked set to fall to near freezing following the storm.

“Colder air will sweep into the Southeast behind the severe weather with temperatures dropping into the 30s (1 C) southward to central Georgia and across most of Alabama by Monday morning,” AccuWeather meteorologist Kristina Pydynowski said.

“Those without power who rely on electric heat need to find ways to stay warm,” she added.

The swath of destruction left by the storm was a quarter mile (0.4 kilometers) wide and stretched for the “several miles that it traveled on the ground,” according to Jones.

Still and video images showed trees that had been snapped in two, debris-strewn roads and wrecked houses in the wake of the storm.

More than 6,000 homes were left without power in Alabama, according to PowerOutage.US, while 16,000 suffered outages in neighboring Georgia.

Authorities warned the death toll could rise further as rescuers search through the debris in Beauregard, about 60 miles (95 km) east of the state capital Montgomery.

Television images showed the heavy rain had relented by dusk but many roads in the worst-hit areas were left littered with debris and unpassable.

Residents in the town of Smith Station told local TV news crews of their shock at turning up to work to find their businesses destroyed, and seeing crying co-workers comforting one another.

One bar in the town appeared to have lost its roof and most of its walls, in images screened by MSNBC, while a cell tower was completely destroyed.

“My sister and niece have been under tornado watch and warnings all day in Montgomery... Prayers up for Alabama,” Emmy Award-winning filmmaker Ava Duvernay tweeted. — Agencies