A super strong winter storm brought significant cooling, cold wind, rain and snow weather to large areas of the United States on the 22nd, seriously affecting people's livelihood and travel before Christmas. According to the announcement issued by the US meteorological department in the evening of the same day, more than 200 million people in the United States are in areas covered by certain winter weather warnings or warnings, including 11 million people in areas covered by snowstorm warnings. This strong polar cold front caused a sudden drop in temperature in the central plains of the United States, with record cooling rates in many places. The temperature in Colorado fell from - 5 ℃ to - 20 ℃ on the 22nd, and the lowest temperature in Wyoming reached - 37 ℃. At the same time, the midwest of the United States and parts of the Great Lakes region are experiencing heavy snow. Officials in New York state said the snowfall in some parts of the state is expected to be as high as 90 centimeters. New York, Kentucky, Georgia, North Carolina, Oklahoma, West Virginia and other states have declared emergencies. Some areas in Colorado, Nebraska, Wyoming and other states were closed due to ice and snow weather. According to statistics from a flight information tracking website, as of the evening of the 22nd, nearly 2300 U.S. domestic and international flights had been canceled and more than 7600 flights had been delayed. American meteorologists believe that the winter storm may also strengthen into a "bomb cyclone", that is, a strong and rapidly developing frontal explosive cyclone on the mid high latitude ocean surface, often accompanied by strong winds, rain and snow, with strong destructive power. On the 22nd, US President Biden asked the White House team to be ready to help the local people fight against the disaster, and called on the people to take the winter storm seriously. (Liu Xinshe)