Most parts of Hunan will be mainly sunny and cloudy due to the subtropical high, with the highest temperature reaching about 39℃.

The Great Heat fell on July 23 and the second of the three ten-day periods of the hot season will come on July 26.

The Great Heat is the time when Hunan gets the most sunshine and the highest temperature in a year. In many areas, the highest temperature is above 35℃ and even 40℃.  

According to the statistics from the China Weather, the average temperature of the Great Heat from 1991 to 2020 is the highest among the 24 solar terms, and the average number of hot days is also the largest.

Changsha is firmly among the 10 sizzling cities.

Although the subsolar point gradually moves southward after the Summer Solstice, the surface heat is still accumulating until the heat accumulation reaches its peak around the sanfu period of the Great Heat.

Especially for the south, it is controlled by the Western Pacific Subtropical High around the Great Heat.

In the places under its control, the prevailing downdraft will increase the ground temperature, and it is not easy to form clouds, making it easier for solar radiation to reach the ground and lead to the temperature rise.

Although high temperature is normal during the Great Heat, it is rare to see such a high temperature as this year.

According to meteorological experts, the surface reason is that the cold vortex is completely defeated by the subtropical high and the Iran High, unable to contain the expansion of thermal forces. But the underlying causes involve circulation pattern, air-sea interaction, climate change and so on.

From today to August 1, there will be little rainfall in the whole province. While showers or thundershowers will be frequent in the northwest of Hunan. Other areas will be sunny and hot with temperature higher than the same period of the year. 

The Hunan Meteorological Bureau continues to issue orange high temperature warnings. It is expected that from 20:00 on July 24th to 20:00 on July 25, the temperature in Changsha, Zhuzhou, Xiangtan, Hengyang, Shaoyang, southern Yueyang, southern Changde, Yiyang, Chenzhou, Yongzhou, Huaihua, Loudi, southern Xiangxi and southern Zhangjiajie will reach more than 37℃ and even 39℃ in some areas.

Meteorological experts remind that attention should be paid to prevent the adverse effects of scorching weather on power supply, production safety and human health, and to avoid heat stroke when working outdoors.

At the same time, it is necessary to guard against the adverse effects of strong scattered rainfall caused by local convection in the afternoon.