Will it be frosty in first frost?
There will still be a few storms, and the hurried autumn will return. Autumn, in a drizzle, went deep and came to first frost.
On the day of first frost, there is no frost, the rain is grey and the fog is boundless. Rain, splashing on the umbrella, swimming on the flat road. The wind blew off the temperature and blew the sleeves.
How did first frost come into being
first frost is a common phenomenon, which contains physical knowledge. The water vapor near the ground will condense, that is, liquefy, because it is cold, so we often see a layer of white things on trees and flowers, which is called first frost!
Time in first frost
The time in first frost is October 22nd, 23rd or 24th every year. The solar term in first frost means that the weather is getting colder and the first frost appears. It is the last solar term in autumn, and it also means that winter is about to begin.
first frost date calculation formula: [Y*D+C]-L
Interpretation of the formula: Y= two digits after the number of years, D=.2422, L= leap years, C=23.438 in the 21st century and C=24.218 in the 2th century.
for example, first frost date in 288 = [88× .2422+23.438]-[88/4] = 44-22 = 22, first frost on October 22nd.
exception: the calculation result in 289 is added by one day.
the origin of first frost
twenty-four solar term said about first frost: In mid-September, the qi was cold and condensed, and the dew was frosty. At this time, frost has appeared in the Yellow River Basin of China, and a piece of silver ice crystal is shining on the field thousands of miles away. At this time, the leaves are yellow and falling. The ancient book "Twenty-four solar terms" said: "Qi is depressed and first frost, and Yin begins to coagulate". It can be seen that "first frost" means that the weather is getting colder and the dew is condensed into frost. In ancient China, first frost was divided into three stages: one was a jackal offering sacrifices to animals; Second, the vegetation is yellow; Three-time stinging insects are salty. The jackal began to capture prey, offering sacrifices to animals, and offering sacrifices to heaven and paying back the book with animals, thus paving the way for offering sacrifices to autumn gold; The leaves on the earth are yellow and fall; The stinging insects are all motionless in the cave, hanging their heads to enter hibernation.