A bitterly cold Arctic air mass has caused temperatures to drop across much of the Northern Hemisphere, where parts of the US are, Canada and Siberia recorded temperatures below minus 40C.
In the United States, the powerful Arctic storm put more than 200 million people, about 60 percent of the population, under weather warnings for the weekend with warnings of life-threatening wind chill, blizzards and ice storms.
Cold weather and danger forecasts extend as far south as the US-Mexico border, the Gulf Coast and Florida, where temperatures are expected to fall below freezing on Christmas Eve.
The weather system, called a “Bomb Cyclone”, is also known as bombogenesis, the term given to an explosive storm that rapidly intensifies. In such storms, temperatures drop as atmospheric pressure drops significantly, usually as a result of a cold air mass from the north colliding with a warm air mass from the south, according to the National Oceanic Service.
The National Weather Service said Friday evening that arctic air will be present across much of the central and eastern U.S. with temperatures well below average, including overnight lows below freezing for many areas of the Midwest, and in the single digits and teenagers elsewhere in parts of the country. southern and eastern USA.
In Chicago, the temperature dropped to minus 23 degrees Celsius in the early hours of Friday morning, and in New York, it moved from 11 degrees on Friday morning to minus 10 degrees by the afternoon, and by Saturday morning it had dropped to minus 14.
Temperatures in Miami dropped from a warm 28°C on Friday to just 5°C overnight on Saturday.
In the northern US, much of Montana and Wyoming saw temperatures below minus 45C, or 15C below the 1981-2010 average.
Patterns of extreme weather are typical of the effects of climate change, although weather attribution experts are cautious about assessing individual events.
However, some meteorologists this week linked the freeze to a changing jet stream that has caused disrupted weather patterns for several years.
Scientists have been trying to understand how an unusual shape in the belt of fast air that controls mid-latitude weather triggers extreme weather events, including heat waves.
US President Joe Biden issued warnings from the White House on Thursday about severe weather conditions that will disrupt much of the country and create life-threatening conditions.
The storm would bring with it strong arctic gusts that would cause sudden lows and zero visibility, the National Weather Service said. Traveling in such conditions would be “extremely dangerous and sometimes impossible.”
“In addition to very cold temperatures, strong winds behind the front will produce dangerous wind chill readings across nearly all of the central and eastern US,” it added, warning that cold temperatures could lead to frostbite on bare skin within five to 10 minutes.
More than 6,300 flights were canceled across the U.S. on Friday, including about 3,600 international flights, according to flight-tracking website FlightAware.
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