Why is the weather in the northeast so cold?

The latitude of northeast China is 40 north latitude. 10, the direct point of the sun moved to the southern hemisphere, far away from the northeast of China. In Northeast China, the height of the sun is obviously reduced at noon, the daytime is obviously shortened, and the solar radiation is obviously weakened. 10 In October, the high pressure in Mongolia and Siberia began to be strong and approached the northeast. The northerly winds in winter affect the northeast earlier, so the cold season in the northeast is longer, and now heating has begun in some areas.