What Does Typhoon Landfall Mean? Does It Weaken Immediately After Landfall?
TyphoonSays·防御问答 · Typhoon knowledge · 更新 at 2026-07-18
What is Typhoon "Landfall"?
In meteorology, typhoon landfall has a clear definition. It does not mean that the entire typhoon center has completely entered the landmass, but rather that the center of the typhoon (i.e., near the eye or the area of maximum wind speed) has moved inland across the coastline. According to the National Standard for Tropical Cyclone Grades issued by the China Meteorological Administration (CMA), landfall is determined when the center position of a tropical cyclone moves from the ocean to the land surface.
For ordinary residents, understanding the "landfall point" is crucial. The landfall point is typically the area with the strongest winds, most concentrated rainfall, and greatest impact from storm surges. However, this does not mean that only the landfall point is dangerous. A typhoon is a massive weather system, with its outer cloud bands and wind circles often covering hundreds of kilometers. Therefore, even if your city is not the direct landfall point, as long as it lies within the typhoon's gale-force wind circle (Level 7) or storm-force wind circle (Level 10), it will still suffer from strong winds and heavy rain. The frequently heard forecast of "expected to make landfall along the coast of a certain area" is a prediction made by meteorological departments based on the typhoon's movement path and speed, aiming to remind relevant areas to prepare in advance.
Does a Typhoon Weaken Immediately After Landfall?
This is a common misconception. Many people believe that a typhoon will "lose steam" and disappear rapidly once it makes landfall. In fact, the changes a typhoon undergoes after landfall are a complex process, and it does not stop causing damage immediately.
Firstly, a typhoon does gradually weaken because it loses its huge energy source—the ocean (warm seawater provides water vapor and heat). At the same time, the rough terrain on land (such as mountains and buildings) increases friction, consuming the typhoon's kinetic energy. However, this weakening takes time and is influenced by various factors:
- Topographical Influence: If a typhoon encounters high mountain ranges, its structure may be rapidly disrupted, causing wind speeds to drop quickly; however, if it moves over plain areas, the typhoon may maintain its intensity for a longer period.
- Water Vapor Supply: If the typhoon continues to access sufficient water vapor after landfall, or combines with other weather systems, its rainfall capacity may not decrease but instead increase, potentially triggering extreme heavy rain.
- Residual Circulation: Even if the wind speed at the typhoon's center weakens to the point where it is no longer classified as a "typhoon," its residual low-pressure system can still bring continuous heavy rainfall for several days, leading to secondary disasters such as flooding or landslides.
Therefore, do not let your guard down just because a typhoon has made landfall. The threat of wind and rain persists until official alerts are lifted.
How to Cope with Risks Before and After Landfall?
Facing typhoon landfall, scientific defensive measures are key to protecting life and property. Before the typhoon arrives, please closely monitor warning signals issued by meteorological departments. Note that specific criteria for school suspensions, work stoppages, and transport halts may vary by location; please refer to notifications issued by local governments and emergency management departments.
Residents are advised to make the following preparations:
- Reinforce Windows and Doors: Check if home windows are secure. Apply tape in an "X" or asterisk pattern if necessary, and remove items prone to falling from balconies, such as flower pots.
- Stockpile Supplies: Prepare at least 3 days' worth of drinking water, ready-to-eat food, common medications, and emergency lighting tools such as flashlights and power banks.
- Avoid Going Out: During typhoon landfall, wind speeds are extremely high, making billboards and trees highly susceptible to collapse. Please stay indoors in safe areas and keep away from windows and doors facing the wind.
Real-time typhoon tracks can be queried at TyphoonSays (taifengshuo.com)
This article is typhoonsay's original copy content, and the local policy standards are based on the local government's latest release.