A polar vortex collapse. Now, meteorologists are calling for another collapse in the middle of March, one that could plunge the U.S., Canada, and parts of Europe into a bitterly cold spell just days before the official arrival of spring.

The National Oceanic and Atmospheric Administration (NOAA) explains that a polar vortex is a large area of low pressure and cold air currents which circulate around both of the Earth’s poles. It has a circular shape and is at it’s peak during the winter months.

What is the polar vortex? The polar vortex is a large area of low pressure, cold air around the Earth's poles that blows westward during the winter

The polar vortex that has dealt the most brutal winter to much of the US in recent years is about to be broken down – but not before unleashing a late-season cold and the biggest yet. A stratospheric warming event has begun,

A polar vortex collapse is expected to bring severe winter weather to Canada and the US mid-month. This event could also affect the UK and Europe, disrupting weather patterns as cold Arctic air spills southward,

A polar vortex collapse is set to bring freezing cold temperatures and travel chaos to large parts of the US and Canada in mid-March, with the UK also at risk of a temperature drop

The Met Office has declared it is "almost certain" that a sudden stratospheric warming will hit Britain in mid-March, potentially bringing a cold snap to the UK. A spokesman for the meteorological service told GB News: "The stratosphere polar vortex is now weakening rapidly.

The seemingly imminent polar vortex collapse will result in arctic air being released into North America, marking the second instance of extreme winter weather this year