Several grades of wind speed

According to the national standard "Wind Grade" issued in June of 20 12, and according to the wind speed at the height of 10 meter in the standard meteorological observation field, the wind grade is divided into 18 grade in turn. There are three commonly used units to express wind speed, namely nautical mile/hour, meter/second and kilometer/hour, and the commonly used unit for typhoon forecast in China is meter/second.

In the weather forecast, we often hear the expression "the north wind is 4 to 5", in which the wind refers to the average wind; If you hear the phrase "gust 7", gust refers to the wind with high and low speed, and the wind at this time refers to the high-speed wind.

Wind power and speed

In daily life, it is easy for us to convert wind power into corresponding wind speed, that is, the distance of air flow per unit time, expressed in m/s, and its conversion formula can be used for reference: two, two to one, three plus one. Grades four to nine are not difficult to calculate, and the series is reduced by two times three. Ten to twelve are rare, so ten is easy to remember.

Ten-level wind speed is twenty-seven, with one more level every four levels. That is, the wind speed of the primary wind is equal to 1 m/s, the wind speed of the secondary wind is equal to 2m/s, the wind level of the tertiary wind is added with 1, and its wind speed is equal to 4m/s, and the series from 4 to 9 is subtracted by 2, and then multiplied by 3 to get the corresponding wind speed. The wind speed algorithm from 10 to 12 is the same. The wind speed of 10 is 27m/s, and then the wind speed of 1 1 is 3 1m/s by adding 4, and the wind speed of 12 is 35m/s. ..