What do you mean by dog days?

The dog days refer to the first, middle and last three days.

Three volts is a general term for initial, middle and final volts. The dog days appear between midsummer and hot summer, which is the time when the temperature is the highest and it is humid and sultry all year round. The word "V" in three volts has two meanings.

First, it means that Yin Qi was forced by Yang Qi to hide underground; Second, it means the weather is too hot to move. The sleeping time is determined by the combination of solar terms and dry branch dates. The dog days are characterized by high temperature, low pressure, high humidity and low wind speed.

Calculation method:

According to the traditional calculation method in China, the third Geng day from summer to the future is the beginning of "initial lodging", the fourth Geng day is the beginning of "intermediate lodging", and the first Geng day after beginning of autumn is the beginning of "final lodging".

Because every Geng day is 10 days apart, the stipulated time of the first day and the last day is 10 days. The number of days in midsummer is long or short, which may be 10 or 20 days, depending on the date of the third Geng Day (the first autumn) after the solar term of summer solstice every year.