What do you mean it's hot?

"Three volts" is the general name of the first, middle and last three volts, and it is the hottest season in a year. It appears from mid-July to mid-August in the solar calendar every year. Its climate is characterized by high temperature, low pressure, high humidity and low wind speed. "V" means being forced to hide underground. According to the climate law of the lunar calendar in China, predecessors have long stipulated that "the third Geng day after long summer begins with the first day, the fourth Geng day begins with the second day, and the first Geng day after beginning of autumn ends with the third day, with the first ten days, the middle ten days, the twentieth day, and the third forty days.