The lower the pressure, the stronger the typhoon.
Pressure is the core indicator of measuring Typhoon Intensity: The lower the air pressure, the greater the difference with the outer perimeter, the stronger the wind speed.
The lower the typhoon, the stronger the pressure.
The lower Typhoon Pressure, the greater the air pressure difference with the outer perimeter (about 1010hPa), the stronger the force that drives the air flow, the greater the wind speed.
Reference correspondence (Northwest Pacific, approximate value) :
| Pressure | Almost intensity |
|---|---|
| 1000-990 hPa | Tropical Storm |
| 990-975 hPa | Severe Tropical Storm |
| 975-955 hPa | Typhoon |
| 955-935 hPa | Severe Typhoon |
| <935 hPa | Super Typhoon |
Historical Value
- The world’s lowest: 1979 Typhoon 泰培 (Tip) , Pressure870hPa, 同时也是范围最大的Typhoon (直径约2200km)
- 2013 Haiyan (Haiyan) : About 890hPa, at peak intensityLandfallPhilippines
- Landfall Typhoon, Wendy in 1962, Rammasun in 2014 (about 910 hPa at Landfall Hainan) are all representatives of extremely low air pressure.
TyphoonSays的史上The most severe typhoon榜按最低Pressure排序, 可以View 完整榜单和每个Typhoon 的路径.
Why Intensity Indicators Use Air Pressure and Not Just Wind Speed
- Air pressure can be measured accurately.The aircraft launched the detector, the ground weather station can be directly measured; while the wind speed is near the center of Max Wind, observation and estimation is difficult.
- Wind speed standards are different.China for 2 minutes on average, Japan for 10 minutes, USA for 1 minute, the same Typhoon for different wind speed numbers, the air pressure is relatively objective.
- Historical comparison: Comparing Typhoon Intensity over the years, Air pressure is the most reliable measure.
Air pressure drops rapidly – increased early warning
If Typhoon Pressure drops more than 20hPa within 24h, the indication is"Rapid Intensification". In recent years, in the context of global warming, the proportion of rapidly enhanced near-sea Typhoon has risen, leaving the time window for coastal defense shorter, which is one of the most concerned risks in modern typhoon forecast.