Researchers told CNN that the winter storm that hit the US this week and over the next few weeks could be linked to the displacement of a massive polar vortex that began in late November.
The polar vortex is a circular flow of strong winds over the Arctic that can trap cold air in that region. However, recently, it weakened and moved southwards towards the mid-latitudes, Bringing cold, arctic air to densely populated areas.
That could lead to stormy conditions as cold air coming from the north collides with relatively warm air, said Andrea Lopez Lang, a meteorologist at the University of Wisconsin in Madison.
And the weak polar vortex also means a wavy jet stream. These are wind currents that blow from west to east in the Northern Hemisphere. A wavy jet stream could leave people weather-beaten, said MIT meteorologist Judah Cohen. For the rest of December, we can expect a continued swing between below average conditions and cooler temperatures due to storms.
However, López Lang cautioned that this polar vortex phenomenon is not the only factor behind the upcoming temperature fluctuations. “It’s certainly contributing, but it’s not the whole story,” she said.
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