What does 300mm of rainfall mean?

The depth of the water layer that falls from the sky to the ground, and the depth of the water layer that accumulates on the surface of the water without evaporation, infiltration, or loss, is called rainfall (in millimeters), which can visually indicate the amount of rainfall. At present, the commonly used instruments for measuring rainfall include rain measuring cylinders and measuring cups. The rain gauge is generally 20 cm in diameter and contains a funnel and a bottle.

The measuring cup has a diameter of 4 cm, and it is used with a rain gauge. When measuring, pour rainwater from the rain scale into a measuring cup, and you can know the amount of rain for the day according to the scale on the cup.

The China Meteorological Administration stipulates that the rainfall within 24 hours is called the daily rainfall, and the daily rainfall is less than 10 mm is called light rain, millimeters are moderate rain, millimeters are heavy rain, heavy rain is millimeters, heavy rainfall is millimeters, and more than millimeters are called extremely heavy rainfall.

Due to the vast territory of our country, a small number of areas have other provisions according to the specific conditions of the province. For example, in the rainy Guangdong, the daily rainfall of more than 80 mm is called heavy rainfall; In the Yan'an area of Shaanxi Province, where there is little rain, the daily rainfall of more than 30 mm is called heavy rainfall.

If you don't have a rain gauge handy, don't worry, you can make your own with some common utensils, and the results are quite good. Take a disposable plastic or paper bowl with a diameter of 20 cm (a suitably sized instant noodle paper bowl is optional), cut a small hole slightly larger than a corn kernel in the bottom, and place the bowl on a jar without a lid. There is a glass bottle inside the jar, and the mouth of the bottle is connected to a small hole in the bottom of the bowl.

The simple rain gauge is ready. Once the simple rain gauge is ready, it can be placed at a height of 70 cm above the ground (the distance between the mouth of the cylinder and the ground) to receive rainwater. When the rain stops, weigh the water in the bottle on a scale, and 30 grams of water is equivalent to 1 millimeter of rainfall.

1.Rainfall refers to the depth (thickness) of the water layer stored (cumulative) in the ground without penetration, loss and evaporation of different forms of precipitation such as rain, snow and hail falling from clouds to the ground.

2.The amount of rainfall is usually measured in millimeters.

3.Rainfall Classification:

Light rain: Rainfall of less than 10 mm on a day (8 a.m. to 8 a.m. the next day).

Moderate rain: 10-25 mm of rainfall per day.

Heavy rain: 25-50 mm of rainfall per day.

Heavy rain: 50,100 mm of rainfall per day. Heavy rainfall: daily rainfall of more than 200 mm.

300 ml of rain in 24 hours.

Rainfall refers to the volume of rain per unit area in a 24-hour period. "200 mm of rainfall" refers to 200 mm of rain on 1 square metre in a 24-hour period. According to the regulations, it reaches the level of heavy rain.

Rainfall is not the intensity of rainfall. Rainfall intensity refers to the amount of rainfall per unit period of time and is measured in millimeters per minute or millimeter per hour.

400 mm of rain has two meanings: one means the amount of rain that falls within 1 hour to 24 hours, which refers to extremely heavy rainfall.

The other means that the average rainfall in the year (month, day) is 400 mm.

Precipitation. precipitation) refers to the depth at which liquid or solid (after melting) water that falls from the sky to the ground within a certain period of time accumulates on a horizontal plane without evaporation, infiltration, or loss. In mm, one decimal place is taken in meteorological observations.

1 mm of precipitation means that the amount of precipitation on one acre of land (666 7 square meters) reaches a depth of 1 mm.

Meteorology. There are often yearly, monthly, daily, 12-hour, 6-hour or even 1-hour precipitation. All the rain and snow that falls during the year melt into water, which is called annual precipitation.

The average annual precipitation of a place over many years is called the average annual rainfall of that place. For example, the average annual rainfall in Beijing is millimeters, and the average annual rainfall in Shanghai is millimeters. According to the meteorological observation specifications, weather stations.

In the presence of precipitation, observations are made every six hours.

According to the intensity of precipitation, it can be divided into: light rain, moderate rain, heavy rain, heavy rain, heavy rain, and extremely heavy rain.

1. Light rain and danpi: 1d (or 24h) rainfall less than 10mm.

2. Moderate rain: 1d (or 24h) rainfall of 10 25mm.

3. Heavy rain: 1d (or 24h) rainfall of 25 50mm.

4. Heavy rain: 1d (or 24h) rainfall of 50 100mm.

5. Heavy rainstorm: 1d (or 24h) rainfall of 100 250mm.

6. Heavy rainstorm: 1d (or 24h) rainfall of more than 250mm.

Rainfall 1mm refers to the water depth of 1 millimeter per unit area, rainfall refers to the depth of the water layer that falls from the sky to the ground, without evaporation, infiltration, and loss and accumulates on the water surface, generally in millimeters, it can intuitively indicate the amount of rainfall. Generally, the commonly used instruments for measuring rainfall include rain gauges and measuring cups, and one decimal place is taken in meteorological observations.

In general, weather forecasts.

The amount of precipitation is time-bound, and it normally refers to 24 hours of precipitation. If the annual precipitation of a place is averaged over many years, it is called a place"Average annual rainfall"。

Rainfall refers to the depth of the aquifer that falls to the ground in a certain period of time, and is expressed in millimeters. The amount of rainfall per unit of time is called rainfall intensity.

Rainfall intensity is classified by rainfall rating. Rainfall is the depth of the water layer that falls on the ground at a certain point or per unit area in a certain period of time, measured in millimeters. According to the regulations, any cumulative rainfall of more than 50 mm in 24 hours is considered a heavy rain.

Rainfall of 250 mm is the concept of a very heavy rainstorm.

Less than 10 mm is called light rain, millimeters is moderate rain, millimeters is heavy rain, heavy rain is millimeters, heavy rain is millimeters, and more than millimeters are called extremely heavy rain.

1. Rainfall, rainfall refers to the depth of the water layer that has accumulated on the water surface without evaporation, infiltration and loss of rainfall from the sky, generally in millimeters, which can intuitively indicate the amount of rainfall. Rainfall is an important basis for calculating regional water resources, so it is necessary to find an accurate and easy way to increase rainfall.

2. Classification criteria, rainfall is an important disaster data, with chaotic characteristics, for the division of rainfall grades, different departments have different standards.

Meteorological Department: Rainfall refers to the depth of the water layer that falls to the surface in a certain period of time, expressed in millimeters. The amount of rainfall per unit of time is called rainfall intensity. Rainfall intensity is classified by rainfall rating.

Flood control department: Rainfall is the depth of the water layer that falls on a certain point on the ground or on a certain unit area in a certain period of time, measured in meters. According to the "Flood Prevention Manual" of the National Defense Office, any rainfall of more than 50 mm in 24 hours is considered a heavy rainfall.

Hydrological Department: Light rain, moderate rain, heavy rain, heavy rain, etc., which are generally measured by daily rainfall. Among them, light rain refers to daily rainfall of less than 10 mm; Moderate rainfall of 10 mm on a day; Heavy rainfall of 25 mm; Heavy rainfall of 50 mm; Heavy rainfall of 100 250 mm; Heavy rainfall of more than 250 mm.

3. Rainfall measurement, rainfall is generally measured with a rain measuring cylinder, so precipitation may contain a small amount of dew, frost and pine. In meteorology, there are often yearly, monthly, daily, 12-hour, 6-hour or even 1-hour precipitation, and the rain and snow that falls in 6 hours all melt into water, which is called 6-hour precipitation; All the rain and snow that falls in 24 hours melt into water, which is called 24-hour precipitation. All the rain and snow that falls in a decade melt into water, which is called the precipitation in the decade. All the rain and snow that falls during the year melt into water, which is called annual precipitation.

The amount of liquid precipitation is called rainfall, and sometimes the two are also used as synonyms. The amount of precipitation per unit of time is called precipitation intensity, which is usually measured in mm h or mm min. The amount of rainfall per unit of time is called rain intensity.