Is the winter solstice the coldest day of the year?

The coldest day of the year is not the winter solstice.

The winter solstice is the year with the shortest day and the longest night in the northern hemisphere. After the solstice in winter, the days will get longer day by day. The ancients said this about the winter solstice: As soon as the cathode arrived, the yang began to grow, the sun went south, the day was short and the shadow was long, so it was called "the winter solstice". After the winter solstice, the climate everywhere has entered the coldest stage, which is often called "entering the ninth". In China, there is a folk saying that "it's cold in March, and it's dog days". According to modern astronomical science, the sun shines directly on the tropic of Capricorn from the winter solstice, and the sun is most inclined to the northern hemisphere. The northern hemisphere has the shortest day and the longest night. After this day, the sun gradually moved to the north. The winter solstice is the shortest day in a year. From this day on, count to nine, or the first day of 1999, the weather will get colder and colder. As the saying goes, the bricks are frozen.

So when is the coldest day? Judging from the solar terms, it should be the coldest day in the Great Cold, which is one of the 24 solar terms. Before 65438+1October 20th every year, the cold wave frequently goes south, which is the coldest period in most parts of China. The wind is strong, the temperature is low, and the snow on the ground does not melt, showing a cold scene of ice and snow. During this period, railway, post and telecommunications, petroleum, shipping and other departments should pay special attention to take measures to prevent severe weather such as strong winds and blizzards as soon as possible. Agriculture should strengthen the cold and antifreeze of livestock and wintering crops.

The cold day must be on March 9, so the coldest day of the year is the cold day.