Why are cities near the Yangtze River usually the hottest in summer and the coldest in winter?

Because of the different latitudes on the earth, the conditions of the four seasons are not the same. Low latitudes are hot all year round, with summer all year round. The high latitudes are cold all year round, and the four seasons are like winter, all of which belong to areas with unclear four seasons. The mid-latitude region can also be regarded as the region with the most "four distinct seasons" between the Tropic of Cancer (23.5) and the polar circle (66.5).

Most of China lies between the Tropic of Cancer and the Arctic Circle, so China is a country with four distinct seasons. In addition, China's monsoon climate belongs to "continental monsoon climate", which makes the climate in the middle and lower reaches of the Yangtze River, North China, Northeast China and Northwest China present the characteristics of "Leng Xia fever in winter" except the Qinghai-Tibet Plateau and the southern coastal areas.

Why are cities near the Yangtze River basin, such as Chongqing, Wuhan, Jiujiang and Nanjing, so hot in summer? Every summer, due to the strengthening of the subtropical high belt in the northwest Pacific, the ridge of high pressure often extends westward, affecting the Yangtze River basin in China and bringing dry weather and high temperature weather in summer. In addition, the Yangtze River basin is a southern water town, and the air humidity is high and humid, which makes people feel even more uncomfortable, so it feels particularly hot.

The middle and lower reaches of the Yangtze River are not only "hot" in summer, but also "frozen" in winter. Why? Obviously, from the absolute temperature value, the temperature in Northeast China, North China and Northwest China, which are closer to the source of cold air in winter than the middle and lower reaches of the Yangtze River, is lower, but the northern region is dry and cold because of less precipitation in winter, and the Yangtze River basin is wet and cold because of more water vapor, which makes people feel colder.

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