What are the standards of light snow, heavy snow, heavy snow and heavy snow?

Light snow: It means that the horizontal visual distance is equal to or greater than 1000 m when it snows, the depth of snow on the ground is less than 3 cm, the precipitation level is 24 hours, and the snowfall is between 0. 1 ~ 2.4 mm..

Snow: refers to the horizontal visual distance between 500 ~ 1000m when it snows, the depth of snow on the ground is 3 ~ 5cm, and the snowfall in 24 hours is 2.5 ~ 4.9 mm. ..

Heavy snow: refers to the poor visibility when it snows, the horizontal visual distance is less than 500 meters, the depth of snow on the ground is equal to or greater than 5 cm, and the snowfall in 24 hours reaches 5.0 ~ 9.9 mm.

If there is snowfall without forming snow, it is generally called "sporadic light snow".

When the snowfall reaches 10.0 ~ 19.9 mm in 24 hours, it is a blizzard, 20.0 ~ 29.9 mm is a blizzard, and more than 30.0 mm is a blizzard.

Extended data

Maintenance matters in snowy days

One of the precautions: improper way to keep out the cold.

Improper way to keep out the cold. Young people who like fashion must pay attention to changing clothes in time when they enter and leave the environment with large temperature difference between indoor and outdoor. On snowy days, in order to pursue fashion, you can't show your legs or wear thin clothes. At the same time, pay attention to a light diet and don't eat too much cold food at a time to prevent acute gastroenteritis.

Note 2: Prevent respiratory diseases.

Prevent respiratory infection. Winter and spring are the high incidence seasons of respiratory diseases. Children, the elderly and patients with chronic diseases with relatively low resistance should appropriately reduce outdoor activities, pay attention to cold and warmth, and maintain regular ventilation indoors.

Note 3: Prevent stomach bleeding and digestive tract ulcer.

Prevent gastric bleeding and digestive tract ulcer. Cold can easily lead to stomach bleeding and digestive tract ulcers, so pay attention to the warmth of the stomach and diet conditioning. The daily diet should be light, light and easy to digest, so as to eat less and eat more, eat regularly, avoid cold diet, quit smoking and drinking, and also choose some Chinese patent medicines that warm the stomach and strengthen the spleen.

Note 4: Prevent gas poisoning.

Prevent gas poisoning. In the cold winter, when using gas and coal stoves for heating, families must pay attention to maintaining ventilation. Pay attention to the safety of heating equipment, remember to exhaust and ventilate frequently, and beware of waste gas accumulation.

Note 5: Prevent accidental falling.

Prevent accidental falls. Rain and snow make the road slippery. Therefore, the general public is specially reminded to pay attention to travel safety and prevent accidental falls.

Note 6: Prevent respiratory diseases.

When the weather gets cold, the first thing to test is the respiratory system. Usually do not pay attention to exercise, coupled with the closed indoor air does not often circulate with the outside world, it is likely to cause upper respiratory tract infection.

Baidu encyclopedia-snow