What is the concept of category five wind?

Level 5 wind refers to the wind speed of 8.0- 10.7 m/s, and the waves in the sea are getting higher and higher, foaming at the peaks and splashing occasionally. Small trees with leaves are swaying on the land, and there are small waves on the inland water.

Meteorology is generally divided into twelve grades according to the magnitude of wind: Grade 0 wind is also called no wind, Grade 2 wind is called light wind, Grade 4 wind is called gentle wind, Grade 6 wind is called gale, Grade 8 wind is called gale, Grade 10 wind is called gale, and winds above Grade 12 are called typhoons or hurricanes.

Typhoon classification

In the past, China used to call the tropical cyclone formed on the tropical ocean surface above 26℃ a typhoon. According to its intensity, it is divided into six grades: tropical depression, tropical storm, strong tropical storm, typhoon, strong typhoon and super typhoon.

According to the notice of National Standard for Tropical Cyclone Grade Implementation (GBT 1920 1-2006) issued by China Meteorological Bureau, tropical cyclones are divided into six grades according to the maximum surface wind force near the center.

Tropical depression, the maximum wind force is 6 ~ 7, (10.8 ~ 17. 1 m/s);

Tropical storm with maximum wind force of 8-9 (17.2-24.4m/s);

Strong tropical storm with maximum wind force10 ~1,(24.5 ~ 32.6 m/s);

Typhoon, maximum wind force 12 ~ 13, (32.7 ~ 41.4m/s);

Strong typhoon with maximum wind force14 ~15 (41.5 ~ 50.9 m/s);

Super typhoon, maximum wind force ≥ 16 (≥ 5 1.0m/s). ?

the typhoon structure

Typhoon is a deep low-pressure system, and its central air pressure is very low. There is an air flow converging towards the center at the lower level, and the air flow at the upper level mainly diverges outward. If the typhoon is cut horizontally, we can see that there are three obviously different areas, from the center to the outside: typhoon eye area, cloud wall area and spiral rain belt area.

Typhoon Eye Area: It's strange that the wind here is very light and the weather is sunny, with an average diameter of 40 kilometers. The sailors who participated in it humorously called Typhoon Eye "Xanadu".

Cloud wall area: the cloud wall area with a width of tens of kilometers and a height of more than ten kilometers around the typhoon eye, also called eye wall. The cloud wall is towering here, the wind is howling, the rain is pouring, the sea is churning, and the weather is the worst.

Spiral rain belt area: Outside the cloud wall, there are spiral rain belts, and several rain (cloud) belts gather spirally around the eye wall. The rain is tens to hundreds of kilometers wide and several Qian Qian meters long. There will be showers and windy weather where the rain belt passes.