When does the dog days start counting?

The dog days are calculated according to the date of solar terms and the date of dry support, starting from "Geng Day".

The temperature is the highest, and the latent time needs to be from summer to the next 20 days. The traditional algorithm "dog days" starts from summer to the third Geng day in the future and ends on the second Geng day after beginning of autumn.

The dog days appear in midsummer and heat. The so-called "dog days" refers to the "dog days" of the lunar calendar, which is the hottest period of the year. It can be understood as "squatting" means that the weather is too hot to move.

But the dog days are called "dog days" because there are also many cold factors. The dog days are the hottest thirty or forty days in a year in the Central Plains. The dog days are calculated according to the lunar calendar, between early July and mid-August in the solar calendar.

Dog days algorithm:

Dog days, one volt is ten days, counted by days. Therefore, the dog days are divided into three days, that is to say, after the third day of Gengtian, the summer solstice is the first day, the first volt.

For example, the summer solstice in 2006 is June 2 1 in the western calendar year, and the dry day of this day is Xinri. 28 days later, it is the third Geng Day. Therefore, July 20, 2006 is the beginning of the first volt. Ten days later, it was another Geng day, that is, July 30, and it entered the second volt.

Ten days later, it was another Geng Day, the first Geng Day after beginning of autumn, that is, August 9, and it entered the dog days; If it is 2007, July 15 is the third Geng day and the beginning of the first volt; Ten days later, it was another Geng day, that is, July 25, and it entered the second volt (middle volt).

Ten days later, it's another watch day, but I haven't been to beginning of autumn yet. Ten days later (there are still 20 days in mid-autumn this year), it will be another Geng Day, the first Geng Day after beginning of autumn, that is, in August of 14, it will enter the dog days.

In other words, every year after the dog days, it is very hot, especially in the middle ten days (sometimes twenty days), which is the hottest. There is a folk saying that "the cold is in the March 9th and the summer heat is in the middle".