Summary: | ABSTRACT: China is frequently affected by tropical cyclones in summer and autumn because its southern and eastern parts border low-latitude oceans. The track forecasting of tropical cyclones is a key issue in weather forecasting. In daily operations, forecasters usually focus on the effects of environmental flow fields on tropical cyclones, such as the subtropical high pressure belt, the basic flow, the troughs and ridges in westerlies, the cross-equatorial flow, the equatorial convergence belt, and the polar front. However, these factors become less significant when the environmental fields are so weak that the steering flow does not play a vital role or we cannot accurately determine the evolution of the environment flow field. Meteorological satellite cloud imagery can fill the data gap of conventional observations and provide important clues for forecasting the status and development of tropical cyclones when they are included in day-to-day weather forecasting operations. In this study, using “Muifa”, “Haikui” and other typhoons as examples, the effects of the cloud pattern and the large-scale environmental vapor fields, on the moving tracks of typhoons were analyzed based on satellite data. The results showed that the change of structures of typhoon spiral cloud bands and the turning of the typhoon path were taking on greater relevance, and at the same time the satellite water vapor images had obvious advantages in terms of indicating the large-scale environmental fields. A combination of satellite cloud imagery, observational data, and weather event analysis remains the most effective approach in the operational forecasting of typhoon moving tracks. Keywords: typhoon, moving track, satellite cloud imagery, environmental field
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