What are the meteorological concepts of rainfall of 50 mm and 100 mm?

Rainfall refers to the depth of the water layer that falls to the ground in a certain period of time, expressed in millimeters. 1mm precipitation refers to the water depth per unit area1mm. 50/ 100 mm means that the water depth per unit area is 50/100 mm.

According to the calculation that 1mm precipitation falls into the field, the area per mu is 666.7m2 Therefore, 1mm precipitation is equivalent to an increase of 0.667m3 of water per mu. Every cubic meter of water is 1000 kg, so the precipitation of 1 mm is equivalent to watering about 650 kg of water per mu.

The rainfall per unit time is called rainfall intensity. Rainfall intensity is classified according to rainfall grade.

Extended data

Division of rainfall intensity in weather forecast

Light rain refers to the rain in which the precipitation does not exceed 10 mm within 24 hours;

Small to moderate rain is 5 mm ~ 16.9 mm, moderate rain is 10 mm ~24.9 mm;

Moderate to heavy rain17 mm ~ 37.9 mm;

Heavy rain 25 mm to 49.9 mm;

The rainstorm is 38 mm ~74.9 mm;

If the rainfall exceeds 50 mm in 24 hours, it is called rainstorm; If it exceeds 100 mm, it is called a torrential rain; If it exceeds 250 mm, it is called rainstorm.

Baidu encyclopedia-rainfall