Nature
Bitter cold has descended on swathes of the US this week, as the nation faces its 10th – and coldest – polar vortex of the season. In a normal winter, you can expect to see this happen two or three times.
The anomalous Arctic chill is set to hit the Central US, bringing record-breaking cold and dangerous wind chills as low as -51°C (-60°F), according to the National Weather Service (NWS). Heavy snow is expected to blanket from Kansas to Missouri on Tuesday, while snow and ice are expected in North Carolina and southeastern Virginia on Wednesday.
“Arctic air will spread across much of the central US into New England this week resulting in record-breaking cold and life-threatening wind chill temperatures,” the NWS adds on its homepage. “Heavy snow will move from the northern Rockies to the central Plains by early Tuesday. A swath of significant snow and ice will likely move from the central Plains to the Mid-Atlantic states Tuesday through early Thursday.”
Extreme cold warnings have been issued in multiple states, stretching from the Canadian border to central Texas.
The cold snap comes as meteorologists predicted a 10th polar vortex this winter. This frigid phenomenon is a low-pressure system of cold air that swirls above Earth’s poles. Alongside the polar jet stream, it helps to trap cold air around the poles, however, it can be disrupted, allowing that air to escape and move into lower latitudes. As it does so, it brings icy weather with it – as we’ve already seen in large parts of the US this season.
Polar vortex activity like this is not abnormal – but happening 10 times in one winter is. And this one looks set to be particularly biting.
“Everything, all the stars align, all the wind directions in the atmosphere are dragging the cold polar air out of the Canadian Arctic,” private meteorologist Ryan Maue, a former NOAA chief scientist, told AP. “It’s the depths of winter. Everything signals extreme biting, winter cold. Obviously, this isn’t the first polar vortex episode of the winter, but it looks to be the most severe.”
On Tuesday, temperatures in the Lower 48 states are expected to have an average low of -8.6°C (16.6°F), which could then plunge to -10°C (14°F) on Wednesday, Maue added.
At some point in the week, 89 percent of the contiguous US will be below freezing, AP reports, with Kansas, Nebraska, Missouri, and Iowa experiencing the brunt of the cold.
Such extreme conditions can be incredibly dangerous – frostbite can occur within minutes so far below freezing, the NWS explains. People are, therefore, being advised to do all they can to keep warm. “Be sure to dress in layers including a hat, face mask, and gloves if you must go outside,” the NWS adds.
