An arctic blast has brought extreme cold, heavy snow and intense wind across much of the U.S.  just in time for the holidays. The weather system, dubbed a “bomb cyclone,” is disrupting travel and causing hazardous winter conditions. Where is this winter weather coming from, and what’s in store for the coming days?

WHAT’S HAPPENING?

A front of cold air is moving down from the Arctic, sending temperatures plunging. Temperatures may drop by more than 20 degrees Fahrenheit (11 degrees Celsius) in just a few hours, the National Weather Service predicts. Wind chill temperatures could drop to dangerous lows far below zero — enough to cause frostbite within minutes. In parts of the Plains, the wind chill could dip as low as minus 70 degrees Fahrenheit (minus 57 Celsius).

What is a bomb cyclone?

A bomb cyclone, which comes from the meteorological term “bombogenesis”, is when atmospheric pressure falls very quickly – at least 24 millibars within 24 hours. In other words, this means that a storm is intensifying fast, which can have more devastating effects than the results of a weaker storm.