Frostfall, the eighteenth of the twenty-four solar terms, is the last solar term of the fall season. Dou refers to the eleventh day of the month; the sun's yellow longitude is 210°; the festival is intersected on October 23-24 of the Gregorian calendar every year. The frosty season is characterized by colder weather in the morning and evening, hotter at noon, and a large temperature difference between day and night.

Because "frost" is a manifestation of cold weather and a big difference in temperature between day and night, the festival is named after "Frost", which means "a sudden drop in temperature and a big difference in temperature between day and night". Frost season, all things Bi into, Bi into the eleventh day of the month, Yang down into the ground, the yin gas began to condense.

Expanded Information

Note:

On average across the country, the Frosty Season is the time of year with the greatest difference between day and night temperatures. The "frost" festival reflects the climate characteristics of plummeting temperatures, large temperature differences between day and night, and obvious autumn dryness. The cold weather begins with the frost.

Frost does not mean that into this festival will be "frost", in fact, "frost" is not from the sky down, "frost" is the ground water due to temperature change encountered cold air condensed into, "frost" festival and "frost" has nothing to do, they are not the same concept.

Baidu Encyclopedia - Frosty Patch