How long did Guangdong Dragon Boat Water last? How is it formed?

Since the May Day holiday, Guangdong, especially Guangdong and Guangxi, has experienced heavy rain. Near the Dragon Boat Festival, the dragon boat water began to arrive. There is always a period of time every year when there is a lot of rain in South China. Do you know anything about dragon boat water?

Introduction to Dragon Boat Water Generally speaking, the annual precipitation from May 2/KLOC-0 to June 20 in Gregorian calendar is called "Dragon Boat Water". During this period, if the process precipitation is ≥ 100 mm and the daily rainfall is ≥50 mm, it is recorded as a "dragon boat water" process.

The "Dragon Boat Water" season is prone to continuous extreme precipitation, so it is necessary to guard against flash floods, waterlogging and geological disasters.

Dragon Boat Festival is one of the traditional festivals in China, and its related customs and activities are well known, such as "Dragon Boat Race" and "Dragon Boat Festival". Because it is the time of dragon boat race, there is a close relationship between precipitation and dragon boat, which can be said to be the product of the combination of weather phenomena and traditional festivals. The so-called "dragon boat water" does not mean the water in the waters where the dragon boat race is held, but a weather phenomenon that affects South China and other places.

Name: It coincides with the Dragon Boat Festival.

Dragon boat water,

There are also nicknames such as "Duanyang Water", "Dragon Precipitation" and "Dragon Boat Festival Water", which generally refer to the strong concentrated precipitation process in South China from late May to early June every year. For the convenience of statistics, meteorological departments generally refer to the precipitation from May 2/KLOC-0 to June 20 as "Dragon Boat Water".

The cause of "Dragon Boat Water" is closely related to the alternating changes of winter and summer monsoon in the South China Sea. In terms of time, the weather in South China is the most complicated period around the Dragon Boat Festival. The South China Sea summer monsoon usually breaks out in mid-May. After the monsoon broke out, it pushed to South China, producing monsoon convective precipitation.

How is "Dragon Boat Water" formed? After all, "dragon boat water" is a rainstorm process, so we must first understand how the rainstorm is formed.

The formation mechanism of rainstorm is quite complicated, but it must meet two important macro conditions: one is rich water vapor source, the other is strong updraft and favorable atmospheric circulation situation, so that the intensity of precipitation is large enough and the duration is long enough.

Coincidentally, these two conditions are met just before and after the Dragon Boat Festival every year.