Why Do Different Meteorological Agencies Produce Different Typhoon Track and Intensity Forecasts?
TyphoonSays·防御问答 · Typhoon knowledge · 更新 at 2026-08-10
Why Are Typhoon Forecasts Like a “Riddle”?
Many residents have noticed that when they open different weather apps or consult bulletins from meteorological agencies in different countries, the predicted track and intensity of a typhoon often differ, sometimes substantially. This is not because any one party has “calculated incorrectly,” but because typhoon forecasting is inherently extremely complex. A typhoon is a giant thermodynamic engine whose movement and evolution are jointly influenced by upper-level steering flows, sea-surface temperatures, vertical wind shear, and surrounding weather systems. At present, no mathematical model anywhere in the world can perfectly simulate every physical process in the atmosphere. Forecasting is therefore essentially a probabilistic scientific estimate rather than an absolute prediction.
Core Reason: Differences in Models and Initial Data
The main reason forecasts differ among countries lies in the use of different “numerical weather prediction models.” Major operational forecasting models worldwide include Europe’s ECMWF, the United States’ GFS, and the CMA-TYM model operated by the China Meteorological Administration. These models differ in their algorithm design, physical parameterization schemes, and treatment of ocean–atmosphere interactions. For example, some models are more sensitive to the strength of the subtropical high, while others place greater emphasis on the thermal structure inside a typhoon.
In addition, small errors in the “initial field” may be amplified. Although meteorological satellites, radars, and weather balloons collect vast amounts of data, they cannot cover every corner of the oceans. If the initial data supplied to a model contain slight inaccuracies, the resulting track and intensity forecasts may diverge significantly after several days of iterative computation on a supercomputer. This is similar to the butterfly effect: small differences in the starting conditions can lead to vastly different outcomes.
How Should Forecast Differences Be Viewed?
When forecasts from multiple agencies differ, the public should focus on the “consensus area” and the “range of uncertainty” rather than debating who is more accurate.
- Look at ensemble forecasts: Modern meteorological services often provide “ensemble forecasts,” which run a model multiple times by slightly adjusting the initial conditions to form a “probability corridor” with a measurable width. A typhoon is most likely to remain near the center of the corridor, but it may also deviate toward its edges.
- Pay attention to sudden intensity changes: Intensity is more difficult to forecast than track. A typhoon may undergo “rapid intensification” or “sudden weakening” within a short period. This often depends on microscale processes such as eyewall replacement cycles, which remain a worldwide challenge.
- Follow official warnings: As a typhoon approaches, local meteorological departments will issue corrections based on actual local conditions. Standards for defensive measures such as school closures and work suspensions may vary by locality, so the local government’s instructions should be followed. During a typhoon’s impact, residents are advised to closely monitor the latest warning signals issued by their local meteorological agency rather than relying solely on long-range forecasts made several days earlier.
Understanding forecast uncertainty helps us maintain a reasonable level of disaster preparedness—neither panicking needlessly nor becoming complacent. Real-time typhoon tracks can be checked on TyphoonSays (taifengshuo.com).
This article is original educational content from TyphoonSays. Please refer to the latest official announcements from local governments for policy standards.