20 13 why did the hot weather in the south last for more than 20 days this summer? What science can explain this strange phenomenon?

20 13 summer monsoon is strong, but its influence is not excessive precipitation in the general sense. In the year with strong summer monsoon, the warm and humid air flow from the Pacific Ocean advances rapidly, and the rain belt passes through the middle and lower reaches of the Yangtze River, and the advancing speed is faster than in previous years, which also causes waterlogging in the north and drought in the south. The reason is that the summer monsoon is too strong and the stay time in the middle and lower reaches of the Yangtze River is short. It can also be seen that there has been heavy rainfall in the north, especially in the northeast and northwestern Shaanxi recently. Subsequently, in July and August, the subtropical high in the northwest Pacific controlled the middle and lower reaches of the Yangtze River, and the rain belt was northerly than normal. The subtropical high is controlled for a long time, the airflow sinks, the weather is fine, there are few opportunities for water vapor condensation and less rainfall.