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🌤 | Typhoon No. 4 will land in Vietnam on the 13th (Sun) tomorrow


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Typhoon No. 4 will land in Vietnam on the 13th (Sun) tomorrow

 
If you write the contents roughly
The central pressure of the typhoon is 996 hectopascals, the maximum wind speed near the center is 18 meters, the maximum instantaneous wind speed is 25 meters, and it is moving west-northwest at a speed of about 1 km per hour.
 

Typhoon No. 12 occurred in the Gulf of Tonkin near Hainan Island, China, at 3:4 pm on Saturday, 996th.The central pressure of the typhoon is XNUMX heks ... → Continue reading

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Wikipedia related words

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wind speed

wind speedWhat is (wind speed)?WindAs空 気MovesSpeedThat is. Japanese Meteorological AgencyThe unit normally used inm / s(So-called speed per second), internationallyknot (kt) is used. For measurementAnemometerIs used.

Overview

In Japan, when we simply say "wind speed", it is about 10 above the ground in surface weather observation.Meters10 at the height ofMinuteAmongAverage wind speedRepresents 0.25secondAverage 3 seconds (12 samples) updated everyInstantaneous wind speedTo say[1].. Also, the maximum value of the average wind speedMaximum wind speed, Maximum instantaneous wind speedMaximum instantaneous wind speed("Instantaneous maximum wind speed" is misused[2]). As the number of high-rise buildings increases in urban areas, it is difficult to accurately measure the wind flow near the ground, so the height is several tens of meters or more above the ground.AnemometerIs often installed.

If you want to measure the wind speed but don't have an anemometer,Meteorological Agency Beaufort ScaleorBeaufort Wind ClassBased on the above, the wind speed is estimated by the wind power judged from the condition of the feature or the sea surface.

The value obtained by dividing the maximum instantaneous wind speed in a certain time by the average wind speed.Gust rateGenerally, it is about 1.5 to 2.0. Also, the wind pressure is the square of the wind speed.ProportionalIt is known that it grows larger.

In general, the average wind speed is faster on the sea than on land, and the gust rate is smaller. Wind speeds range from global atmospheric conditions to structural atmospheric turbulence caused by buildings.(I.e.Affected by the difference.

It can be said that a constant wind speed is maintained throughout the year in western Europe, where westerlies constantly blow due to the influence of the global atmospheric conditions. Smaller examples are highs and lows,typhoonThe wind speed observed when a tropical cyclone such as is approaching is relatively fast. Tornadoes are a prominent example of smaller ones, with maximum instantaneous wind speeds exceeding 100 m / s being observed. Also,High-rise buildingIn the area whereBuilding styleBlows.

Classification by wind speed

Classification

Wind powerWind speed of 10m above the ground (or more)Typhoon classification (maximum wind speed)
00.0 m / s (0 knot)
10.3 m / s (1 knot)
21.6. m / s (4 knot)
33.4 m / s (7 knot)
Four5.5 m / s (11 knot)
58.0 m / s (17 knot)
610.8 m / s (22 knot)
713.9 m / s (28 knot)
817.2 m / s (34 knot)
920.8 m / s (41 knot)typhoon
1024.5 m / s (48 knot)
1128.5 m / s (56 knot)
1232.7 m / s (64 knot)Strong typhoon
43.8 m / s (85 knot)Very strong typhoon
54.1 m / s (105 knot)Furious typhoon
1 kt = 0.514 m / s = 1.852 km / h = latitude 1 minute / h
1 m / s = 1.944 kt = 3.6 km / h

In this table, "typhoon(Classification of tropical cyclones occurring in the northwestern Pacific Ocean, based on the Japan Meteorological Agency) ”only shows the classification of wind speed.

ス ケ ー ル

Atlantic and northeastern PacificHurricaneStrength classificationSafa Simpson Hurricane ScaleClassifies hurricanes into five categories, Category 1 to Category 5, according to the estimated maximum wind speed. It is a tornado strength classificationFujita scale(F scale),Improved Fujita Scale(EF scale) is also classified by the estimated maximum wind speed.

Japanese Meteorological Agency

In addition, the following are expressions of wind strength used in the announcements and weather forecasts of the Japan Meteorological Agency and each meteorological station.

PerformanceDefinition
QuietWind speed less than 0.3m / s
Slightly strong windWinds of 10 m / s or more and less than 15 m / s
Strong windWinds of 15 m / s or more and less than 20 m / s
Very strong windWinds of 20 m / s or more and less than 30 m / s
Fierce windWind speed of 30 m / s or more or maximum instantaneous wind speed of 50 m / s or more

Beaufort scale

The following Beaufort scales are also used[3].

NameWind powerSpeed ​​per second (m / s)Status
No wind00.0-1.4 Smoke goes straight up
Soft wind11.5-3.4 Feel the wind
Japanese style23.5-5.9 Move the leaves of the tree
Gale36.0-9.9 Move tree twigs
(I.e.410.0-14.9 Move the branches of a tree
Storm515.0-28.9 Move the trunk of a tree
hurricane629.0 and overDefeat trees and houses

Wind speed record

Japan

世界

footnote

  1. ^ World Meteorological OrganizationStandards of. Japan Meteorological Agency2007May 12This is adopted from. It is about 0.25 to 6% smaller than the conventional method that takes a single value every 10 seconds, but a gust is added to buildings etc.workThe size of can be reflected more accurately.
  2. ^ Japan Broadcasting Corporation. "Which is correct, "maximum instantaneous wind speed" or "maximum instantaneous wind speed"?". 2012/11/2Browse.
  3. ^ Paper industry summary Oji Paper 1938
  4. ^ Info note No.58 "World Record Wind Gust: 408 km / h" World Meteorological Organization
  5. ^ a b Highest surface wind speed --Tropical Cyclone Olivia sets world record World Records Academy

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