How is the rainstorm formed? How many millimeters of rain does a rainstorm mean in 24 hours? Can you talk about it?

1. Typhoon: The typhoon brings a lot of water vapor from the ocean, and the violent movement of the atmosphere is easy to form heavy rain.

2. Cold and warm: The cold air mass meets the warm air mass, forming a cold front and forming a rainstorm in a short time.

3. Temperature: In summer, the temperature is high, and the water vapor evaporates vigorously, forming convective movement and producing heavy rain.

Heavy rain refers to how many millimeters of rainfall there are in 24 hours.

According to China's meteorological regulations, rain with precipitation exceeding 50 mm within 24 hours is called "rainstorm", so the hourly rainfall of rainstorm is at least 2.08 mm. The causes of rainstorm are: sufficient water vapor, strong updraft, unstable atmospheric structure, and water droplets in the cloud constantly expand under the action of updraft until the updraft can't hold up and falls to the ground sharply, forming a rainstorm.

Rainstorm level: it is divided into three levels according to its precipitation intensity, that is, the 24-hour precipitation of 50 ~ 99.9 mm is called "rainstorm"; /kloc-below 0/00 ~ 250 mm is "rainstorm"; More than 20 mm is called "rainstorm". Early warning signal: The rainstorm early warning signal is divided into four levels, which are represented by blue, yellow, orange and red respectively. Rainstorm is a kind of disastrous weather with serious influence. In a certain area, continuous rainstorms or torrential rains often lead to flash floods, reservoir dam breaks, rivers flooding, houses being washed away, farmland being flooded, traffic and telecommunications being interrupted, which brings serious harm to the national economy and people's lives and property. In particular, heavy rain, especially large-scale persistent heavy rain and concentrated heavy rain, not only affects industrial and agricultural production, but also may endanger people's lives and cause serious economic losses.

Is rainstorm a force majeure factor?

According to relevant regulations, a rainstorm must reach a certain level before it can be considered as force majeure. Force majeure has three elements: unforeseeable, inevitable and insurmountable. Generally refers to earthquakes, mudslides, wars, plagues, etc. Rainstorms are usually not force majeure. Because the rainstorm only meets the standard of "inevitable", it does not necessarily meet the standards of "unforeseeable" and "insurmountable". For example, sign a contract with the developer and hand over the house one year later. Within this year, if it is in the south, there will definitely be several heavy rains. Developers themselves should also consider the impact of heavy rain, which is called "foreseeable"; What's more, not the rainstorm will definitely affect the construction period, at least the indoor engineering will not be greatly affected, which is called "overcoming".