...
By Thomas Westerholm
Life & Trends Reporter
0
Share
Newsweek is a Trust Project member
See more of our trusted coverage when you search.Prefer Newsweek on Googleto see more of our trusted coverage when you search.
A disruptive polar vortex is set to usher in three successive waves of Arctic air across the central and eastern United States through mid-December, bringing dangerously low temperatures and the potential for heavy snow.
According to forecasts from AccuWeather, the first wave of cold began sweeping through the Midwest earlier this week, with subzero temperatures forecast for states including North Dakota, Minnesota, Iowa and Nebraska.
Meteorologists expect a second and third Arctic blast to follow over the next two weeks, bringing hazardous travel conditions and increased energy demands.
Read More on Life
"The polar vortex is particularly disruptive this winter," Rick Shema, consulting member of the Association of Certified Meteorologists, told Newsweek in an email.
...
What is a Polar Vortex?
A polar vortex is a large, low-pressure system of cold air that typically resides near the Earth’s poles, surrounded by strong westerly winds in the upper atmosphere.
"In the northern hemisphere winter, a strong, stable polar vortex keeps colder air contained well north," Shema told Newsweek.
"A disruption in the strength of the vortex produces waves of instability in the circulation that causes it to dip southward.
"This is the current state of the polar vortex now; an unstable, wavy pattern. These waves bring outbreaks of very cold, Arctic air that moves southward over the continental United States.
Shema compared a polar vortex to a, "large salad bowl of cold air," in the email to Newsweek.
"The sides of the bowl contain the cold air in a circular pattern over the polar region," he said.
"If the sides of the bowl break and crack, this allows cold air to spill out and affect the surrounding area."
'Coldest in years'
The cold surges will challenge infrastructure across large swaths of the country. Nighttime lows are forecast to dip into the single digits and teens as far south as the central Plains and interior Southeast, with wind chills making it feel 10 to 25 degrees colder than actual temperatures.
Energy consumption is expected to spike across affected regions. Homeowners and municipalities are being urged to winterize homes, prepare heating systems and brace for power grid stress as heating demands climb.
Shema said we are experiencing more extreme weather than usual this December.
"The extremeness lies in the recurrence of frequent cold air surges," he said.
"This is because the polar vortex is weak and unstable allowing colder air from the Arctic region to repeatedly plunge southward over the continental United States.
"This December will likely be one of the coldest in years. Cold air temperatures most likely will be broken."
What to Know
The polar vortex has weakened and shifted southward, enabling cold air masses to spill into the U.S.
The leading edge of the current Arctic front brought flurries and snow squalls across the Great Lakes and Northeast from Wednesday into Thursday.
Accumulations may be limited in some areas, but lake-effect snow could bring several inches in places like western New York and Pennsylvania. Later waves may bring more widespread and prolonged snowfall events.
The cold will also push into the Southern U.S., bringing hard freeze risks to areas of the Southeast that are unaccustomed to such conditions in early December.
What’s Next
Forecasters expect the next Arctic wave to arrive early next week, followed by a third system shortly after.
AccuWeather warns that storm tracks remain uncertain, but travelers should prepare for potential delays by road and air into mid-December.
"Along with extreme cold air, there is likely to be higher amounts of snowfall than usual," Shema said.
"Wind chill factor will be key to watch out for too. Even a light breeze can drop wind chill to hazards levels. Keep exposed skin covered.
"As with any prognosis, there is some level of uncertainty in how the polar vortex will ultimately shape up, but conditions are prime for extreme cold and higher snow accumulations than average for December."
To read how Newsweek uses AI as a newsroom tool, click here.
View 0 Comments
Submit Correction
View Editorial & AI Guidelines