According to AFP, a phenomenon known as a “bomb cyclone” is responsible for the extremely cold weather in North America.

According to the US National Weather Service, this once-in-a-generation storm has already smashed cold weather records and may turn lethal in the upcoming days. The regions of  Western Canada recorded minus 53°C, Minnesota experienced -38°C, and Dallas experienced -13°C.

Even subtropical northern Florida had experienced unexpected snowfall. The Whether experts explained that when air pressure decreases by 20 millibars or more in less than 24 hours, a rapidly increasing storm develops into a bomb cyclone.

On this particular occasion, Arctic air and tropical air from the Gulf of Mexico met to create a depression that delivered snow and rain.  According to meteorologist Jan Amis, what makes this storm exceptional is how quickly the pressure dropped – 40 millibars in 24 hours.

Cyril Duchesne, a meteorologist with the French weather channel, said that “this resulted in the emergence of extremely severe storm conditions.”

According to Duchesne, the severity and extremeness of the storm’s frigid temperatures are what give it its unheard-of characteristics.

A “polar vortex dip” is when a particularly cold air mass from the Arctic is pushed south into lower, warmer latitudes as a result of the storm. Temperatures drop as a result; in Denver, for instance, they fell 33oC in just seven hours.

The US National Weather Service has warned that extreme cold can cause hypothermia, frostbite, and even death if a person is exposed to it for an extended period.