Winter Storm Tracker: Cold, Snow And Rain To Sweep US And Canada – The New York Times

Over 100 daily cold temperature records could be tied or broken over the next few days, according to forecast data from the National Weather Service.

Brian Hurley, a senior forecaster for the service’s Weather Prediction Center in College Park, Md., said that the gravest concerns at this time were for blizzard conditions, as well as the precipitous drop in temperature and wind chill expected across several states.

“It’s going to be very cold during the day,” Mr. Hurley said.

Here’s a breakdown of how each region could be affected:

The West and the Plains

The “record-breaking” cold air mass has already enveloped some parts of the region between the Rocky Mountains and the Sierra Nevada, as well as the Central Plains, and will chill the Southern Plains by late Thursday, according to the National Weather Service. Temperatures across the region have already plummeted to minus 10 to minus 20 degrees, with bone-chilling wind gusts of up to 60 miles per hour creating wind chills as low as minus 40 degrees, forecasters say.

In Cheyenne, Wyo., the cold air moved swiftly, dropping a record 40 degrees in just 30 minutes — from 43 degrees to three on Wednesday afternoon. The temperatures have continued plummeting, reaching as low as minus 13, with wind chills feeling more like minus 40 early Thursday morning.

In some parts of this area, the wind chill could reach as low as minus 70 degrees, according to the Weather Service. Without adequate precautions, these conditions can cause frostbite in under five minutes, said the service, “with hypothermia and death also possible from prolonged exposure to the cold.” There is also concern for the welfare of livestock, especially if there is a widespread loss of power.

Brief bursts of moderate to heavy snow lasting an hour or two are likely to occur immediately behind the Arctic front. These so-called snow squalls, when combined with strong wind gusts, can cause whiteouts, leading to “extremely hazardous” travel conditions, the Weather Service said.

Late Wednesday, more than 100 vehicles were reported stuck near Rapid City, S.D. The Pennington County Sheriff said all the stranded drivers had been accounted for within a few hours.

The Pacific Northwest

While the majority of the coastal West, including California, will be spared the bitter cold and punishing weather, some parts of Oregon and Washington State could experience “significant freezing rain,” the Weather Service said, with the potential for ice accumulation to create dangerous travel conditions and scattered power interruptions. Wind chill warnings have also been issued for parts of Washington State.

Texas and the Southeastern United States

On Thursday evening, temperatures in Texas and the Gulf Coast will likely be in the single digits and teens, about 20 to 30 degrees below normal, forecasters say. The temperatures could drop rapidly, and in some parts of the region, could remain below freezing for two to three days, according to the Weather Service.

Wind chill watches and advisories are in effect for much of the Southeastern U.S. In parts of Texas, wind chills — a measure of what the combination of temperature and wind feels like to human skin — could reach a dangerous minus 15 degrees, the Weather Service said. It advised residents to avoid extended time outdoors, and, if they have to brave the cold, to cover exposed skin.

“We’re actually looking at windshield down into the single digits, even some areas are expected to be down in the negative values,” Sam Marlowe, a forecaster with the Atlanta National Weather Service office, said. “Most people here are not used to that.”

This is a one-in-several-year event, he said.

The Midwest

Subzero to single-digit temperatures are expected throughout much of the Midwest, according to forecasters. Vast portions of the region are also under winter storm and blizzard warnings. Such conditions can greatly impair visibility and travel.

In Illinois, the Weather Service warned of bitter wind chills of minus 15 to minus 35 degrees from Thursday night into Saturday, and snowfall of up to four inches on Thursday. Blizzard conditions, the service said, would be possible from Thursday through Friday night.

The heaviest snowfall, according to forecasters, is likely to occur between Wednesday night and Friday over the Great Lakes, where the total depth could exceed a foot. Wind gusts of more than 50 m.p.h. will create near-zero visibility, leading to what the Weather Service described as “dangerous, to at times impossible, land and air travel.” There is also concern for tree damage and widespread power failures.

But the snow doesn’t have to be heavy to become dangerous. Snow combined with 50 m.p.h. winds across the Plains, through the Midwest and into the Great Lakes will create blizzard conditions with any snow falling or on the ground already.

The potential for this to be a “bomb cyclone,” which is meteorologist jargon for a storm system that drops 24 millibars (a measure of air pressure) or greater in 24 hours or less, will lead to extreme winds across the region.

Cities across the region, including Cleveland and Peoria, Ill., are preparing to open warming centers to allow residents to seek shelter during the storm.

Northeastern United States

By late Thursday or Friday, the storm system will have reached the Mid-Atlantic, bringing with it moderate to heavy rainfall of one to three inches, forecasters say. Strong southerly winds, combined with the new moon-tide cycle, could also bring coastal flooding from northern New Jersey to northeast Massachusetts, the Weather Service said.

In parts of Vermont and Maine, heavy rain over a fresh snowpack could lead to flooding, according to the service. Parts of the central Appalachians may also receive light freezing rain and locally heavy snowfall on Thursday morning.

Buffalo and the surrounding area are under a blizzard warning, with the worst hitting them Friday night into Saturday. Meteorologists warned local residents that this is not a normal lake effect event with a narrow band of heavy snow. Instead, the moderate to heavy snow will be more widespread.

“True blizzard conditions are rare in Western N.Y.,” forecasters in the Buffalo, N.Y. weather office warned, “and it’s unusual to even consider blizzard headlines this far in advance of a storm. However, the magnitude of this storm justifies this consideration.”

On Friday, as the Arctic cold front races eastward, temperatures will drop suddenly from the mid to upper 50s down to the 20s or the teens, the service said. This rapid plunge in temperature can flash freeze wet surfaces like roads and pavements, creating hazardous conditions.

A flash freeze occurs when moisture on surfaces like roadways doesn’t have time to evaporate before temperatures quickly dive below freezing, creating black ice conditions.

Canada

While a bout of extreme cold grips western Canada, eastern provinces, including Ontario, should expect a mix of snow and rain on Thursday, followed by plummeting temperatures, heavy bursts of snow and gusty winds over 60 m.p.h., meteorologists say.

“With that quick transition from above zero to below zero, we’re looking at potentially iced roads in some places as well, so extremely difficult travel conditions across southern Ontario,” said Steven Flisfeder, a federal warning preparedness meteorologist.

At Toronto’s Pearson International Airport, which is Canada’s busiest transportation hub, travelers are bracing for cancellations and delays. Heavy snowfall near Vancouver International Airport has already led to the cancellation or delay of hundreds of flights.

The intensity of the snowfall is expected to subside by Saturday evening in Ontario and Quebec, though flurries and snow squalls remain possible in the region surrounding the Great Lakes, forecasters said.

Vjosa Isai and Judson Jones contributed reporting.

That freeze led to at least 250 deaths and caused extensive damage to the state’s power infrastructure.

As global emissions of heat-trapping carbon dioxide continue, the Arctic is warming nearly four times faster than other parts of the planet, according to the latest analysis, and the region’s sea-ice coverage is shrinking. So when the vortex meanders southward, two basic questions arise. What role, if any, does climate change play? And will extreme freezes increase as warming continues?

The short answer: Scientists aren’t sure, yet. There are clues, but still more to learn.

“I wish I had a clear answer,” said Steve Vavrus, a climate scientist at the University of Wisconsin. With Jennifer Francis, now at the Woodwell Climate Research Center in Massachusetts, Dr. Vavrus wrote a seminal 2012 paper that presented the idea that Arctic warming was affecting the polar vortex. “Unfortunately the state of things is still ambiguous,” he said.

What is the polar vortex, exactly?

The vortex is a mass of high-altitude, rotating air that, as the term suggests, occurs over the North Pole region. (There are actually two vortexes, one in the Arctic, the other in the Antarctic, but only the northern one affects weather in the Northern Hemisphere.)

The vortex strengthens and becomes much colder in winter, because with the Northern Hemisphere tilted away from the Sun at that time of year, little or no sunlight reaches the Arctic to warm it up.

If you were looking down at the North Pole, the air would look like it was rotating counterclockwise. Some scientists have compared it to a spinning top. The vortex is encircled by the polar jet stream, a band of winds that blows from west to east around the planet.

What happens during a deep freeze?

In normal conditions, the vortex is stable and confined to the Arctic. But just as a spinning top can start to wobble and drift if it bumps into something, the vortex can be disrupted. It is accompanied by changes to the jet stream, which develops a wavy, snakelike pattern as it circles the globe.

Sometimes the vortex splits into several fragments that move southward. Sometimes, as appears to be the case this week, it becomes stretched, like a rubber band. Either way, the disruption can have several major effects.

Temperatures in the atmosphere over the Arctic can rise, sometimes dramatically. At the same time, the frigid Arctic air moves southward.

If the movement is rapid enough, temperatures in the areas exposed to the mass of cold air can fall by tens of degrees within hours, and can stay extremely low for days or even weeks until the vortex becomes stable again in the North Pole region.

How does the vortex get disrupted?

For climate scientists, this is the crux of the debate.

Some scientists say Arctic warming is causing disruptions in the vortex, through the changes in the polar jet stream. Others say that modeling suggests naturally variable factors are driving disruptions instead and that an increase in vortex disruptions that occurred previously — including a noticeable uptick in the 2000s — has not continued.

Judah Cohen, a climate scientist at Atmospheric and Environmental Research, a weather-risk assessment firm in Lexington, Mass., is an author of a paper this year that linked the 2021 Texas freeze to Arctic warming. He sees the same thing happening now.

The basic idea, he said, is that the warmer conditions create larger and more energetic atmospheric waves that make the jet stream wavier, with greater peaks and troughs. That affects the polar vortex circulation.

To use the spinning top analogy, “it’s like if it started banging into things,” he said. “It loses its nice circular shape and in this case becomes more stretched out.” One lobe stretches down into Canada and the United States, bringing an outbreak of cold weather.

Dr. Cohen said he’s been studying the subject since 2005, and is more confident than ever about the link to changes in the Arctic. “The evidence is only growing,” he said.

Other scientists are not as certain. In a brief paper in the journal Nature Climate Change in 2020, two researchers at the University of Exeter in England wrote that, although Arctic warming and sea-ice loss were continuing, the short-term trends in cold extremes, jet-stream waviness and other climate-related measurements in the 1990s and 2000s “have not continued over the past decade,” weakening the argument that rising temperatures in the Arctic were the culprit.

Some experts suggest that rather than warming, other naturally variable elements of the earth’s climate may be affecting the vortex. Among these, said Ted Shepherd, a climate scientist at the University of Reading in England, are sea-surface temperatures in the tropical Pacific Ocean, which can drive changes to air masses in the Arctic that disrupt the jet stream and vortex.

Will this debate get resolved?

Scientists say that questions over what role Arctic warming may play in extreme cold snaps is an example of the kind of healthy climate-change debates that occur now. It’s not about whether climate change is real — that question has been answered — but what kinds of effects it has, how severe they are and whether they will worsen as warming continues.

Most scientists view this debate as an important one that is still underway. Dr. Vavrus said that some aspects “are on pretty solid physical footing.” Among these, he said, is the idea that Arctic warming, by reducing the temperature difference between the Arctic and the tropics, has weakened the jet stream winds. But other aspects, including whether and where warming is making the jet stream wavier, “are the things that we’ve really been wrestling with and remain uncertain,” he said.

“In the early days there was a lot of black and white thinking, including among people like myself, on this question,” Dr. Vavrus added. “As more and more evidence has come in, it’s clear that there are many shades of gray.”

As the powerful storm approaches, the warnings have grown increasingly ominous. Even in places where bitter cold and heavy snowfall are facts of life this time of year, officials and forecasters have cautioned residents to expect something particularly severe.

In Buffalo, the National Weather Service described the coming event as a “once-in-a-generation storm.” In Cheyenne, Wyo., forecasters said the cold front had swept in and immediately broken records as the temperature dropped from 43 degrees to 3 degrees in a half-hour.

“First of all, it’s wintertime — we expect snow, we expect cold weather,” Gov. Jim Justice of West Virginia said in a briefing as he announced that he had mobilized emergency resources in the state. “It’s going to get pretty tough,” he said. “That’s all there is to it.”

The conditions arrive at a particularly inopportune moment, coming during a busy week of holiday travel, toward the end of Hanukkah and extending through Christmas Day on Sunday. The storm could most likely lead to substantial flight delays and cancellations at some of the nation’s busiest airports and create havoc on the roads.

Wind chills as low as 70 degrees below zero are possible in the High Plains, and subzero to single-digit temperatures are expected throughout much of the Midwest, forecasters said.

In the Central and Southern Plains, a cold front is expected to sweep through the region from Wednesday to Friday, causing dramatic temperature declines of as much as 20 degrees within hours, which could bring flash freezes to roads, the National Weather Service warned. Light to moderate snowfall is expected in the Midwest, Great Lakes region and parts of the Northeast. The Great Lakes may see more than a foot of snowfall between Wednesday evening and Friday.

In West Fargo, N.D., Ostrom’s Hardware has been quickly selling through its supply of snow shovels, snowblowers and ice melt. “Yesterday, we had no shovels on our racks,” said Levi Kraig, the store’s assistant manager.

Cities across the Midwest, including Cleveland and Peoria, Ill., prepared to open warming centers to allow residents to seek shelter during the storm.

In North Carolina, Gov. Roy Cooper signed a state of emergency on Tuesday to begin preparations for icy conditions and high winds expected to arrive on Friday and continue through the weekend.

In Texas, forecasts have evoked the lingering trauma from a monster winter storm last year that shoved the state’s power grid to the brink of collapse, stranding millions of people without electricity amid freezing conditions, and contributing to the deaths of nearly 250 residents.

On Wednesday, state officials sought to assure residents that a repeat disaster could be avoided because the power grid could withstand the jump in demand as people hunkered down in their homes. Demand is projected to be at its highest on Friday morning, officials said.

Texas was not expected to see much, if any, snow or ice, but temperatures were expected to drop into the single digits in parts of the state’s panhandle, forecasters said.

“I think trust will be earned over the next few days as people see that we have ultracold temperatures and the grid is going to be able to perform with ease,” Gov. Greg Abbott said in a news conference on Wednesday.

The storm is expected to hit hardest in places that are accustomed to serious winters.

“We had a blizzard last week with between 24 and 30 inches of snow,” said Emily Larson, the mayor of Duluth, Minn. The coming storm is not expected to bring nearly that much snow, but it will bring strong winds, which, when combined with the snow already piled on the power infrastructure, could greatly raise the risks of major power outages.

“I’ve been mayor for seven years, and I think we’ve had four storms that have severely impacted our community in ways that have been scary,” Ms. Larson said. “It isn’t a great feeling when people don’t have power and heat.”

In Milwaukee, where forecasters have warned that strong, snow-blowing winds will be the primary hazard of the coming storm, city officials gathered at a fire station on Wednesday to prepare residents for storm and cold.

“It is Wisconsin — we do have these exceptional cold snaps, so we do have plans in place to work through these things,” Assistant Chief Joshua Parish said. “But those things take time.”

While a bout of extreme cold grips western Canada, Ontario and its eastern provinces are bracing for a major winter storm expected to hit on Friday. Forecasters there said the region could expect a mix of snow and rain on Thursday followed by plummeting temperatures, the prime conditions for a flash freeze.

Already, heavy snowfall near Vancouver International Airport on Tuesday prompted an “unprecedented number” of canceled flights, the airport said.

In Kentucky, as Gov. Andy Beshear declared a state of emergency and warned residents of the potential danger, he noted that it threatened to add to the litany of catastrophes that have struck his state in recent years. “After tornadoes and floods, pandemics, multiple ice storms just these last three years,” he told residents, “I don’t want to lose one person to this Arctic front that’s coming through.”

In eastern Kentucky, communities that have already been hobbled by decades of economic decline are now trying to claw their way back from devastating floods this summer.

Gwen Johnson, who runs a community center in one of the hollows that was particularly ravaged by the summer flooding, said that most of the people she knew had power but that many houses had not been completely rebuilt to withstand the coming onslaught of cold.

“We had substandard housing before the flood. Then it about knocked out what we did have,” she said. “So a lot of people haven’t gotten their places put back.”

She and others at the center have given out lots of blankets and propane heaters, and she has plans to make a big Christmas dinner for anyone who can make it on Sunday. It was a reflection, she said, of what people there have always done in hard times — rely on each other.

“If there’s no power, the ones that do have power usually take in people,” she said. “We’re no strangers to this.”

Jesus Jiménez and Vjosa Isai contributed reporting.

And it’s all just in time for the holiday travel rush.

Whether you are planning to travel by plane or by car over the Christmas weekend, you could face delays, cancellations and treacherous conditions.

The weather could create more chaos at airports, which AAA, the automobile association, said will be “packed” during the holidays. Nearly 7.2 million Americans are expected to fly between Dec. 23 and Jan. 2, which is 14 percent more than last year and almost as many as in 2019, according to AAA.

Should you cancel your trip? What are your options if your flight is delayed or canceled? Here’s what you need to know if the holiday storm upsets your travel plans.

Know your rights

If the prospect of getting stuck is too daunting, many airlines, including United, American Airlines and JetBlue, are offering to rebook passengers on other flights without additional fees — if they are flying to or from areas that are expected to be hit by severe weather.

But first check the details with your carrier, because each airline has different parameters on when passengers can reschedule their flights.

If your flight is canceled, airlines are obligated by federal law to provide a full refund if the passenger requests it, said Scott Keyes, the founder of Scott’s Cheap Flights, a service that tracks and emails airfare deals to customers. This is true even if a flight is canceled because of the weather.

“It’s still not your fault as a traveler, and you are still entitled to a full cash refund if you want one,” Mr. Keyes said.

If a flight is “significantly delayed,” airlines may also provide a refund if you decide not to fly, Mr. Keyes said, though they are not required to do so. Airlines define what a “significant delay” means though two or three hours for a domestic flight should be a good rule of thumb.

To know what your carrier’s policies are, consult the Department of Transportation’s online dashboard, which features 10 U.S. airlines with green check marks next to the services they offer when flights are delayed or canceled for reasons that the airline controls, such as staffing.

In August, the agency said that it is working on a rule change that would require airlines to refund passengers whose departure or arrival times are delayed by three hours on domestic flights or six hours on international flights.

Use your leverage

Mr. Keyes said this could be an opportunity to take advantage of the expected chaos. If your airline is dropping change fees, it may be possible to get on a better flight than what you originally booked.

Airlines would much rather keep your money than fork over a refund, so “they will work with you to switch to a better flight,” he said.

Another tip: You can try calling an airline’s international hotline, not the U.S. number, even if the canceled flight was domestic, he said.

“Most airlines have numbers all over the world,” Mr. Keyes said. “They’ll have agents there whose lines are empty. They can all help get you rebooked just the same.”

Passengers who booked with online travel agencies, like Expedia, will have to work through those agencies for refunds or to make flight changes, he said.

Be prepared

Install a flight tracker app on your phone, or use your airline’s app to monitor your flight and set up alerts so that you get information as early as possible.

Knowing a flight is going to be delayed or even canceled can help passengers act quickly, said Kathleen Bangs, a spokeswoman for FlightAware, a flight tracking company.

“Then you can be first in line — or first on the phone or on your app — to make arrangements for another flight,” she said.

Passengers who become stranded at the airport may also be able to negotiate with airlines for vouchers, Ms. Bangs said, even though airlines are not required to offer them when weather causes a delay or cancellation.

Ms. Bangs said more airlines are empowering their employees to make decisions at the gate or on the phone to help customers, a philosophy espoused by Herb Kelleher, the founder of Southwest, who focused heavily on customer service.

Customer service agents may be willing to upgrade a stranded passenger’s seat, give them more miles on their mileage plan or provide a hotel voucher even if they are not obligated to, Ms. Bangs said.

“They might say, ‘Well this is a weather event so we’re not offering anything,’” she said. But “it never hurts to ask in a polite way.”

What if I’m driving?

There are two reasons your car trip might be delayed: heavy traffic and weather.

Even if the weather is clear in your location, expect congestion, especially on those days when holiday travelers share the road with regular commuters.

About 102 million people plan to drive 50 miles or more from their homes between Dec. 23 and Jan. 2, according to AAA. That’s 3.6 million more than the number of people who drove during the holiday season in 2021 and nearly as many as in 2018, when 102.5 million people hit the roads. (The record was set in 2019, when 108 million people drove between Christmas and New Years Day.)

In major metro areas like New York City and Los Angeles, travelers could face traffic delays that are twice as long as usual, according to INRIX, a transportation analysis agency.

If you can, drive on Christmas Day, said Bob Pishue, a transportation analyst at INRIX.

But if you have to leave before that, avoid driving between 4 p.m. and 7 p.m. on Dec. 23, and between noon and 6 p.m. on Christmas Eve, when regular commuters are still expected to be on the road, he said.

“If schedules allow, leave bright and early or after the afternoon commute,” Mr. Pishue said.

The cold, ice and snow won’t help. In some parts of the country, the warnings about freezing weather are downright frightening.

In parts of Texas, “dangerously cold wind chills” are possible Thursday and Friday, while the Midwest could see blizzard conditions on Thursday.

AAA “strongly recommends drivers pack an emergency kit,” said Aixa Diaz, a spokeswoman for the group.

The kit should include a cellphone charger, a flashlight with extra batteries, a first-aid kit, reflectors, an ice scraper or snow brush, a shovel, drinking water, extra snacks and food for everyone in the car, including pets if they are traveling with you.

Drivers should have warm gloves, clothes, hats and blankets for everyone in the car. They should also clean their headlights, replace old wiper blades and inspect their tire pressure on their vehicles.

Drivers are also advised not to use cruise control in slick conditions and to stay in their lane as much as possible, since there may be patches of ice between lanes.

“If you hit a patch of ice and begin to skid, try to stay calm and resist the urge to slam on the brakes,” Ms. Diaz said. “Instead, look where you want the car to go and steer in that direction.”

Most importantly, she said, “if there is a blizzard in your path, stay home.”

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For those in the affected areas, forecasters warn that when the Arctic air swings through, it will arrive quickly, with temperatures dropping 25 to 35 degrees in only a few hours.

The system is also expected to plunge temperatures below freezing as far south as Texas and Florida, and produce powerful winds across a large portion of the country.

For many Americans, the lousy weather will threaten holiday travel and make leaving home treacherous. But for thousands of others, whose jobs place them on the front lines of the weather, the storm will mean a particularly challenging, uncomfortable and perhaps dangerous week at work.

Rory Wolters

It has already been a busy year for Rory Wolters and his crew, which is in charge of keeping the runways clear at Gerald R. Ford International Airport in Grand Rapids, Mich.

But after two significant storms earlier in the season, Mr. Wolters, a field maintenance supervisor, said this week’s weather could be the worst of all.

When the storm hits Michigan, likely on Thursday and Friday, Mr. Wolters’s team will fan out across the runway in specialized plows that include brooms on the back. Others will follow behind with high-powered blowers and sand.

“My staff is looking forward to this: This is what we prepare for every year,” said Mr. Wolters, who will lead 12-hour shifts that start at 3:30 a.m. “These guys are excited. We wait for big storms like this.”

Thursday afternoon into Friday morning, the storm will rapidly strengthen across the Midwest and Great Lakes. As it does, it will produce winds strong enough that even small amounts of snow could greatly reduce visibility.

For those passing through the Grand Rapids airport this week, Mr. Wolters had just one request.

“Be patient,” he said. “These guys are putting a lot of hours in. It’s very stressful out there. Visibility out there can be very low. Just bear with us.”

Seth Sprouse

When nasty weather blows through Wisconsin, Seth Sprouse knows his phone could ring at any hour with word of a power line that needs to be repaired.

“If the storm comes in, in the middle of the night, and the outages start rolling in, you just go get your truck from the shop,” said Mr. Sprouse a lineman with Alliant Energy in the Beloit, Wis., area.

A winter storm watch was already set to take effect in Wisconsin on Thursday, with the possibility of blizzard conditions and wind gusts that could down trees and lead to power outages. As the system gets closer, Mr. Sprouse said, linemen will start following outage maps in other states to get a sense of what might be store in for them.

“It’s definitely hard to be away from your family, especially during the holidays, and it’s challenging to be out in the cold and stay motivated,” he said. But, he added, “there’s a lot of satisfaction in showing up to something that’s a big mess on the ground and by the time you leave, you’ve got it fixed and the lights are back on.”

Though people in Wisconsin are used to winter weather, this system could also create power challenges in states far less accustomed to freezing temperatures, including Texas, where many remain traumatized by the failure of the state’s grid during a winter storm in February 2021.

Forecasters and energy experts said the weather in Texas was not predicted to be as cold and snowy as last year, when the power went out for days in huge portions of the state and hundreds of people died. The head of the Electric Reliability Council of Texas, which manages most of the state’s electric power, called the grid “resilient and reliable.”

But the grid is not the only worry in Texas. As hundreds of migrants continue to arrive at the southern border, freezing temperatures could create dangerous conditions for those wading across the Rio Grande or sleeping on the streets in border cities like El Paso.

Wendy Daniels

Holidays often lead to a rush of customers at the Breakthrough Fresh Market food pantry on Chicago’s West Side, where ham, turkey and eggs for Christmas dinners have been in high demand this week.

“They’re already sort of choosing between, ‘Hey, do I pay my light bill or buy groceries?’” said Wendy Daniels, the associate director of food services at Breakthrough. “So now it’s like, ‘Do I pay my light bill, buy groceries or try and get my daughter something for Christmas?’”

But Ms. Daniels said severe weather could pose a barrier to receiving that assistance. She was expecting an influx of customers on Thursday, just as the storm starts bearing down on Chicago. By Friday, the National Weather Service warned that travel in the city could be difficult to impossible and that the cold could be life-threatening.

Many of the volunteers who bag groceries at Breakthrough are older and have trouble getting there in rough weather, Ms. Daniels said. So do some of the customers, many of whom walk to the food pantry or arrive on public transit.

Ms. Daniels still planned to be there.

“I can’t be tired,” she said, “because it’s what I’m called to do.”

Sgt. Ted Bohner

For Christmas travelers making their way through north-central Indiana this week, and for the state troopers patrolling those roads, it would be hard to imagine a more daunting forecast.

“The timing, in my opinion, couldn’t be worse,” said Sgt. Ted Bohner of the Indiana State Police.

Dealing with snowy roads, and with the Christmas travel rush, comes with the territory of being a state trooper. But this storm, Sergeant Bohner said, was particularly worrisome, with the potential for high winds, sustained snowfall and rapidly falling temperatures that could leave a layer of ice on the highways, all on one of the busiest travel days of the year.

“Wind chills of this magnitude can cause frostbite in less than 5 minutes if precautions are not taken,” forecasters at the Weather Prediction Center, a part of the National Weather Service warned.

For Sergeant Bohner, that means routine parts of his job can become potentially deadly ones.

“What could typically be an inconvenience like changing a tire on the side of the road, with visibility and the cold temperatures, could be a life-and-death situation,” he said.

Sergeant Bohner said people planning to travel in his region on Friday should reconsider their holiday plans. His plans have changed, too. Instead of being on vacation on Friday, as he had planned, he will be at work on Indiana’s snowy highways.

Judson Jones, J. David Goodman and Taylor Glascock contributed reporting.

The National Weather Service said the storm dropped a record amount of snow for the region in a 24-hour period — 21.5 inches on Saturday. The previous record was 7.6 inches on Nov. 19, 2014, during a storm that left more than 86 inches by its third day. This has been the area’s second-snowiest November on record, with 36.9 inches.

Still, many Buffalo residents took the storm in their stride. John D’Aquino, 23, a law student at the University at Buffalo, trudged through the snowbanks to get a cup of coffee from a local shop before walking back to his apartment to watch the Buffalo Bills game. The street where he lives was unplowed, with several vehicles on the shoulder of the road still encased in snow.

“There’s nothing like a Buffalo winter,” Mr. D’Aquino said.

Mark C. Poloncarz, the Erie County executive, said during a news conference Sunday morning that much of the region had already been cleared of snow, and that a driving ban on some of the worst-hit roads could be lifted within two days. He said the county has become much more nimble in dealing with weather events, noting that after a similar storm in 2014 many county roads were closed for a week.

“At this point eight years ago, we were just basically finishing up with the snow, and we really hadn’t gotten to recovery efforts and cleanup efforts yet,” Mr. Poloncarz said. “And here we are, eight years later, with having had more snowfall in a shorter time period in most of the areas that were affected, and we are much better along.”

Some school district officials were even contemplating holding classes as usual on Monday. Lisa Chimera, the deputy county executive, said superintendents held a meeting Sunday morning over Zoom to consider their options, though several have already chosen to close schools.

The storm was blamed for killing two people “as a result of snow-blowing, snow-shoveling issues,” Mr. Poloncarz said, urging residents to be careful when clearing driveways and encouraging them to check on neighbors. There were 280 people rescued in the area, and some 1,600 without power. Five buildings collapsed under the weight of snow, the Weather Service said.

The storm, which dumped up to five inches per hour at times, left the biggest overall total in Orchard Park, a suburb southeast of Buffalo — exactly 80 inches, or more than six and a half feet. Although the Weather Service has not determined if the storm broke any statewide records, county officials believe snow totals will exceed the storm of 1966, when 50 inches fell on Oneida County in a day. Unconfirmed reports on Saturday suggested more than that amount fell in Orchard Park on Friday.

The more recent snowfall has been powdery and easier to clear, but expected wind gusts could create drifts that limit visibility. Crews are also struggling to break through densely packed snow and ice beneath the surface.

On a sunny day in the town of Amherst north of Buffalo, winds whipped clouds of snow off the top of the roof outside a local hockey rink and across the parking lot below.

As people in this suburban community continued to clean up driveways and vehicles from the storm, many of the main roadways were completely cleared.

“I like the snow. I like Buffalo weather,” said Lany Mankowski, a retired federal government employee who was watching her 10-year-old grandson play hockey inside the Northtown Center at Amherst on Sunday. “People just take it in stride.”

A few miles away on Buffalo’s Main Street, roads were covered with slush, and many people were still digging their way out.

Gov. Kathy Hochul, a Democrat and Buffalo native, declared a state of emergency for 11 counties, including some adjacent to Lake Ontario in New York’s northern border with Canada. During a news conference on Sunday, Ms. Hochul said she had asked federal emergency officials for help paying for recovery efforts. She said she also plans to ask for federal aid for small businesses that were hurt by the storm.

“As someone who’s from Buffalo and has lived in upstate my entire life, we’ve seen a lot of snow,” Ms. Hochul said. “But when you hit 80 to 85 inches over the course of, you know, just a couple-of-day snow event, everywhere from Natural Bridge up in the North Country to Orchard Park, that is one to tell your grandkids about.”

Elijah Cap, 21, an accounting student at the University at Buffalo who works part time at a supermarket, missed his 6 a.m. shift because he was buried in too deeply. He said the storm was “pretty average” by the city’s standards.

“I don’t think it was anything crazy,” Mr. Cap said. “Main Street is always a mess in the winter.”

But first, a caveat: Check the weather forecast before hitting the road, they said. If a snowstorm is expected, it is best to stay put.

For those who venture out anyway, here are some important safety tips should disaster strike.

Pack a ‘go bag.’

Some important essentials to bring are food, water and a charged cellphone, said Dr. Ken Zafren, an emergency medicine professor at Stanford University and an emergency physician at the Alaska Native Medical Center in Anchorage, Alaska.

Beyond that, experts said it would be helpful to have the following: parkas, blankets, sleeping bags, boots, mittens, hats, flares, medications, wipes, a shovel, a first-aid kit, a cellphone charger, an ice scraper, jumper cables and a full tank of gas.

Even better: Keep these items in your car year-round, experts said.

Stay warm.

You are on the road. Snow is blanketing the ground. Traffic is gridlocked. What now?

First, do not leave your car, experts said. It is the safest place to be until the storm dies down.

“No matter how cold it is inside the car, it will be colder outside,” said Gordon Giesbrecht, a professor at the University of Manitoba who has studied human responses to extreme environments.

Resist the temptation to head out and find help, he added. If you go outside, you could get hypothermia or become lost.

Instead, generate heat by turning on the car for up to 10 minutes every hour, said Dr. Steve Mitchell, a medical director at the Harborview Medical Center’s emergency department in Seattle. Any longer could waste gas.

Human bodies naturally generate warmth, although younger people lose heat faster, he added. Wear a hat so you do not lose heat from your head.

Dr. Giesbrecht suggests maximizing your body heat by hugging your chest and putting your hands in your armpits.

There is only one situation in which you should step outside: if you need to check that your tail pipe is clear, to eliminate the risk of carbon monoxide poisoning from exhaust, experts said.

Take care of yourself.

It is easy to feel isolated or scared, but remember that you are surrounded by other people who are also stranded, said Dr. Grant Lipman, the founder of the Global Outdoor Emergency Support, an app that offers tips for emergencies.

If you have them, eat foods that are high in fat and carbohydrates, which will give you energy and help generate warmth, he added. That includes nuts, chocolate and candy bars.

If you run out of water, drink melted snow, Dr. Mitchell said. But don’t drink alcohol. It will disorient you.

Have wipes and a bottle handy if you need to go to the bathroom, Dr. Lipman said.

While your phone may provide a needed distraction, it is important to preserve your battery so that you can make emergency calls, he said. Close your browser and any other battery-draining apps.

Instead, you can distract yourself by doing small exercises in the car, which will also help you stay warm, Dr. Lipman said.

What about pets?

Lean breeds, older dogs, and puppies are more susceptible to hypothermia, according to the American Kennel Club.

Experts said you should include items for your pets in your emergency kit, such as a blanket and food. While in the car, you could huddle with your pet for warmth. Ideally, you can cover the pet with some form of insulation.

Be visible to rescuers.

When your engine is running, turn on your hazard lights or dome lights so rescuers can see you, experts said.

The National Weather Service suggests tying a bright-colored cloth to your antenna or door. When the snow lets up, raise the hood to signal for help.

Driving when the storm passes.

Drive slowly to avoid skidding, and note that it takes longer to decelerate in icy road conditions, according to AAA. Accelerating too rapidly can cause wheels to spin out of control.

Maintain distance from other cars, trucks, and snow plows.

Tire pressure drops in cold weather. Drivers should inspect tires monthly and before long trips, according to guidance issued by the National Highway Traffic Safety Administration.