What does summer mean? The hot summer is coming to an end.

Being in the heat is "out of the heat", that is, out of the heat. The arrival of the summer heat means that the hot and difficult weather has come to an end and the summer heat has gradually subsided. Although the weather is still hot, it has shown a downward trend.

Summer solar terms are in the period of short-term high-temperature weather (autumn tiger), which generally occurs between August and September in the Gregorian calendar. The duration of autumn tigers generally ranges from half a month to two months. The significance of summer heat in daily life is to remind people that the summer heat is gradually disappearing and the weather is turning from hot to cold, so we should pay attention to preventing "autumn dryness". There are many folk activities in summer, such as eating ducks, setting off river lanterns, opening fishing festivals, decocting medicinal tea and offering sacrifices to the land.

The weather characteristics of summer solar terms weaken the radiation.

It is not enough to describe the solar terms in summer simply by the beginning of temperature drop. Temperature drop is just one of the phenomena. The reasons behind this phenomenon are as follows: first, the direct point of the sun continues to move southward, and the solar radiation weakens; Second, the subtropical high moved southward by leaps and bounds, and the Mongolian cold high began to itch to try, punching and kicking, showing its edge.

A dry and warm climate in late autumn

Autumn Tiger occurs after beginning of autumn in 24 solar terms, which is a short-term high temperature weather. It is as overbearing as a tiger, so people call it "autumn tiger". It usually occurs between August and September, and the duration of autumn tiger varies from year to year, usually lasting for half a month to two months. Although the temperature is high, generally speaking, the air is dry and sunny, and the temperature difference between morning and evening will not be too high. The reason for the autumn tiger weather is that the subtropical high, which was withdrawn from the south, resumed control again, resulting in high temperature and hot weather with crisp weather and strong sunshine. The reason for the formation of autumn tiger is that the western Pacific subtropical high that controls China gradually moves southward in autumn, but moves northward. Under the control of this high pressure, it is partly cloudy, sunny to sunny, with strong sunshine and rising temperature. Although it is autumn, it is sultry.

Although the subtropical high, which is dominant in summer, strides south, it will never give up its advantage easily and retreat to the sea of the western Pacific easily. In the southern region under its control, people who just feel a little cool in autumn often feel hot weather in late summer, which is a veritable "autumn tiger". For areas that have just stepped out of the dog days and suffered from severe summer drought, if they continue to be controlled by subtropical high, it is often easy to form drought in summer and autumn, which greatly advances the fire prevention period in autumn and needs vigilance. What needs to be said is that the middle and lower reaches of the Yangtze River often welcome the crisp autumn spring after the autumn tiger weather, but it will wait until after 10. During this period, the general trend of rainstorm in all parts of the country weakened.

dry

The cold high pressure that began to affect our country, under its control, formed sinking dry cold air, which first announced the end of the rainy season in northeast, north and northwest China. During the hot summer, the only places where the temperature dropped significantly were the northeast and northwest regions. But whenever cold air affects China, if the air is dry, it will often bring windy weather, and if there is warm and humid airflow in the atmosphere, it will often form a decent autumn rain. After every storm, especially after the rain, people will feel more obvious cooling. So there is a saying: "an autumn rain (wind) is a cold." There may be a large precipitation process in the north and south Jianghuai areas. The temperature dropped significantly, and the temperature difference between day and night increased. It is sunny after the rain, and people often don't adapt to the cold and hot changes at the turn of summer and autumn. If you are not careful, it is easy to cause diseases such as respiratory tract, gastroenteritis and cold.

Thunderstorm activity

South China, Southwest China and West China.

Thunderstorms are not as active as in summer, but there are still many thunderstorms in South China, Southwest China and West China. In the south of China, there are more thunderstorms than in other places because the warm and humid airflow at low latitudes is still active. In the southwest and west, there are more thunderstorm activities due to the subtropical high edge and mountains. In September, most parts of China began to enter a period of little rain, while there were more autumn rains in West China. This is a special weather phenomenon in autumn in western China. The scope of autumn rain in West China includes autumn rain in Sichuan, most of Guizhou, eastern Yunnan, western Hunan and western Hubei, in addition to the Weishui and Hanshui basins. Early autumn rain will appear in late August. The earliest appearance date can sometimes start from the end of August and end in the end of 165438+ 10 at the latest. But the main rainfall period occurs in September and June, 10. The main feature of "Autumn Rain in West China" is that there are many rainy days, and another feature is that it mainly rains in Mao Mao, so although there are many rainy days, the rainfall is not very large, generally less than that in summer, and the intensity is weak.