The first polar vortex of the winter season is about to blast the U.S. later this week. By Tuesday, temperatures will fall below zero into the northern plains and the Midwest. Eventually, the cold air will make its way towards the Northeast. Already parts of the U.S. are experiencing winter already. In Montana, temperatures dropped to minus 3 for the first time since January of 2015. All of North Dakota is currently under wind chill advisory.
A polar vortex is an upper-level low-pressure area near a pole. There are two polar vortices on Earth one on the North and the other on the South Pole. With a polar vortex is a large mass of cold, dense Arctic air. It can strengthen or weaken from year to year. If a vortex is strong and well-defined, the cold air is well contained. If the vortex is weak, it will push south towards the equator and bring rapid and sharp temperature drops. The air in the polar vortex came from Siberia and northern Canada. While the polar vortex is always present, it is in the winter when it makes its appearance in the United States.
According to The Washington Post, weather models suggest that temperatures in the Midwest will take a “nose-dive,” with lows below zero from minus 15 to minus 5 degrees. Usually, during this time of the year the average is 20 to 35 degrees more. From there, the polar vortex moves to the Mid-Atlantic and Northeast regions. Temperatures will “struggle to climb above freezing.”
In 2014, the polar vortex came south through the Midwest bringing the coldest weather in two decades, Reuters reported. The vortex lasted until March of that year and caused roads to ice over and delayed or canceled flights. Farmers struggled to keep livestock and crops alive. This vortex killed nine people and affected around 200 million people. The current polar vortex coming now will be similar in “scale and magnitude,” reported USA Today.
Starting Monday, the polar vortex is predicted to arrive in the Midwest. Tuesday, the vortex pushes eastward. Wednesday the vortex arrives in Chicago and Minneapolis and sweeps through the Northeast on Thursday. Many major cities in the Midwest are bracing for the massive temperature drop. According to The Weather Channel, temperatures will be “dangerously cold in some areas.” Factor in the wind chills, many will be affected. Fortunately, the polar vortex will not stay until Christmas, reported USA Today.
By Cheryl Werber