Which solar term is wind and cloud?

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The first frost is the eighteenth of the twenty-four solar terms and the last solar term in autumn. Fight with your fingers; The solar calendar is 210; Celebrate every year on Gregorian calendar 10 year1October 23rd-24th. After entering the first solar term in first frost, the scene of late autumn is obvious, and cold air moves southward more and more frequently.

The first frost does not mean "frost", but refers to the sudden drop in temperature and the large temperature difference between day and night. On the national average, "first frost" is the season with the largest temperature difference between day and night in a year.

In the first frost season, it's all over. From the morning, the sun went down to the ground, Yin Qi began to condense, and the first frost weather became colder and colder. Because "frost" is a manifestation of cold weather and large temperature difference between day and night, it is named "first frost", which means "sudden drop in temperature and large temperature difference between day and night". The first frost solar terms are characterized by cold weather in the morning and evening, hot weather at noon, large temperature difference between day and night, and obvious autumn dryness.

The first frost is the last solar term in autumn and the transition from autumn to winter. In the first frost season, everything is finished, everything goes to heaven, the sun goes to the ground, and the yin begins to condense. The cold weather began with the first frost. Yizhoushu Zhou said: "Autumn and March are empty: summer, autumn equinox, first frost."

In Lun Heng, Wang Chong of the Eastern Han Dynasty said: "Clouds and fog are also signs of rain, while summer is dew, winter is frost, temperature is rain, cold is snow, and rain and dew are frozen, all from the ground, not from the sky." Whether it is dew or frost, "it comes from the ground, not from the sky." How can it be called first frost? In fact, the name "first frost" is only used to describe the climate characteristics of "sudden drop in temperature and large temperature difference between day and night" in this season.

After the first frost solar terms, cold air activities become more frequent, and the temperature difference between day and night becomes larger. The "first frost" solar term has nothing to do with "first frost", which does not mean that entering the first frost solar term will lead to "first frost". In fact, "frost" does not fall from the sky, but the water vapor on the ground condenses when it meets cold air due to temperature difference changes.

There is no concept of "first frost" in meteorology. Generally speaking, the first frost in autumn is called "first frost" or "first frost", and the last frost in spring is called "late frost" or "final frost". The interval from the last frost to the first frost is a frost-free period. In the first frost season, most parts of the north have been harvested in autumn.

Even cold-resistant onions can't grow any longer, because "the first frost can't support onions, and the longer they grow, the more empty they are." In the south, it is the peak season of "Sanqiu". Only single-season hybrid rice and late rice are harvested, and early-season wheat and early-season rape are planted. Picking cotton, pulling cotton stalks, ploughing and soil preparation.