The classification system for typhoon intensity and size defined by the Japan Meteorological Agency.
Overview
Typhoon Classification (Intensity and Size)
The Japan Meteorological Agency classifies typhoon intensity and size separately as indicators of approximate strength. 'Intensity' is classified as 'Strong' at 33 m/s or above, 'Very Strong' at 44 m/s or above, and 'Violent' at 54 m/s or above. 'Size' is classified as 'Large' when the radius of the gale-force wind area (15 m/s or above) is 500 km or more, and 'Very Large' at 800 km or more. These classifications are combined to create expressions like 'Large and Strong Typhoon' and are widely used in disaster prevention information.
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gale-force wind area
storm wind area
| code | slug | name | description | categoryType | windSpeedMaxKt | windSpeedMaxMps | windSpeedMinKt | windSpeedMinMps | windRadiusMaxKm | windRadiusMinKm | windSpeedThresholdMps |
|---|---|---|---|---|---|---|---|---|---|---|---|
| intensity-strong | intensity-strong | Strong | Intensity category for typhoons with maximum wind speeds of 33-43 m/s (64-84 knots). | Intensity | 84 | 43.9 | 64 | 33 | |||
| intensity-very-strong | intensity-very-strong | Very Strong | Intensity category for typhoons with maximum wind speeds of 44-53 m/s (85-104 knots). | Intensity | 104 | 53.9 | 85 | 44 | |||
| intensity-violent | intensity-violent | Violent | Intensity category for typhoons with maximum wind speeds of 54 m/s (105 knots) or higher. | Intensity | 105 | 54 | |||||
| size-large | size-large | Large | Size category for typhoons with a gale-force wind area (15 m/s or higher) radius of 500-799 km. | Size | 799 | 500 | 15 | ||||
| size-very-large | size-very-large | Very Large | Size category for typhoons with a gale-force wind area (15 m/s or higher) radius of 800 km or more. | Size | 800 | 15 |