Arctic blast and blizzard will bring dangerous cold to eastern US

A severe snow and ice storm followed by brutally cold conditions will soon hit the eastern two-thirds of the United States as frigid air escapes from the Arctic and sinks as far south as Florida, forecasters predict.

Starting Saturday, millions of people will be affected by moderate to heavy snowfall from Kansas City to Washington, including a high chance of at least 8 inches of snow between central Kansas and Indiana, the National Weather Service warned Friday. Dangerous ice, particularly lethal to power lines – “as heavy as pasta, it’s hard to move,” said private meteorologist Ryan Maue – is likely to form just south of Kansas, Missouri, Illinois, Indiana and much of Kentucky and the west. Virginia.

“It’s going to be a disaster, a potential disaster,” Maue said. “This is something we haven’t seen in quite some time.”

National Weather Service meteorologist Alex Lamers said Friday that the potential for blizzard conditions is increasing, particularly in Kansas and neighboring parts of the Central Plains, and that wind gusts could reach 50 mph at times.

As the storm moves on Monday, hundreds of millions of people in the eastern two-thirds of the country will be plunged into dangerously cold air and wind chills all week, government and private forecasters said. Temperatures could be 12 to 25 degrees Fahrenheit (7 to 14 degrees Celsius) colder than normal as the feared polar vortex spreads from the high Arctic causing cold weather, they said.

“This could lead to the coldest January for the United States since 2011,” AccuWeather Director of Forecast Operations Dan DePodwin said Friday. “It’s not just one day of this. “There will be three to five, in some cases a week or more, of temperatures well below the historical average.”

The biggest drop below normal is likely to be centered in the Ohio Valley, but significant unseasonable cold will extend south to the Gulf Coast, said Danny Barandiaran, a meteorologist with the National Weather Service’s Climate Prediction Center.

The forecasts have moderated somewhat compared to last week, when some computer models predicted the worst cold wave in decades. Now it is unlikely that many records will be broken, but it will still have a big impact on the country, Barandiaran said.

There should even be a hard freeze in Florida, while areas near the Canadian border will be around zero, Barandiaran said.

“It’s not going to thaw for a while,” Maue said.

Woodwell Climate Research Institute climate scientist Jennifer Francis said the initial strong northerly winds may surprise people after a fairly warm last couple of years.

“The wind chill is going to be brutal,” he said. “There will be a lot of complaints, but it’s winter. … Just because the planet is warming doesn’t mean these cold snaps are going away.”

This double dose of bad weather may be caused in part by a rapid warming of the Arctic, serving as a not-so-kind reminder that climate change drives weather extremes, even winter ones, said Francis and Judah Cohen, director of seasonal forecasting. of the private company. Atmospheric and Environmental Research firm.

The polar vortex, ultracold air that spins like a top between 15 and 30 miles high, usually remains locked over the North Pole. But sometimes it escapes or spreads to the United States, Europe or Asia. And that is when a large number of people suffer intense doses of cold.

Cohen and his colleagues have published several studies showing an increase in the stretching or shifting of the polar vortex. Cohen, Francis and others last month published a study that attributes these cold outbreaks in part to changes in an Arctic that is warming four times faster than the rest of the world.

The change in temperature and the loss of sea ice in the Arctic make the jet stream (the river of air that moves storm fronts) more wavy, allowing gusts of cold air to head south and the weather extreme remains, Francisco said.

What is about to happen “is a very good example of this type of case,” Francisco said.