https://www.weatherzone.com.au/news/record-challenging-cold-snap-gripping-united-states/533499Record-challenging cold snap gripping United States
BenDomensino, Monday February 15, 2021 - 14:44 EDT
The terms'historic' and 'polar vortex' are getting a good workout in the United Statesthis week as a frigid Arctic air mass sends shivers across the country.
Back in January,the air high above the North Pole began to suddenly warm up and slow down (it'susually really cold and windy up there).
This 'suddenstratospheric warming' event quickly caught the attention of meteorologists andclimate scientists around the world, because they can be a trigger for majoroutbreaks of cold weather near the ground.
In the weeks thatfollowed last month's sudden stratospheric warming, this is exactly whatstarted to happen.
Pools of cold airthat are usually bottled up over the Arcticmanaged to escape and spread towards the south. These vagrant Arctic air massesare now causing temperatures to plummet in some parts of the northernhemisphere, even challenging cold-weather records in a few locations.
All weatherrecords are worthy of attention, but cold-weather records are happening lessfrequently in the modern climate and are arguably more impressive thanhot-weather records.
Image: Despitenotable cold outbreaks like this one still occurring, the lowest annualtemperature in Houston, Texas has been getting warmer in recentdecades. Source: Climate Central
There have alreadybeen reports of record-breaking low temperatures in the United States amid thisblast of Arctic air, including a bone-numbing -51ºF (-46.1ºC) at Bottineau,North Dakota on Saturday.
The map belowshows a tongue of cold polar air passing over the United States on Sunday.
Image: Cold Arcticair (white) spreading over the United States on Sunday, according to the ECMWFmodel.
In Texas, emergency warmingcentres have been set up to provide shelter for homeless people and strandedmotorists caught out by snow and ice-covered roads.
On Sunday night, winter storm warnings stretchedover 3000 km from New Mexico up to Vermont.
The severe coldsnap will persist well into the new week as Arctic air continues to surgeacross the United States.
