Relationship between Tropical Cyclone Size Asymmetry and Anomalous Motion

Challenges persist in accurately predicting sharp changes in tropical cyclone (TC) motion over a short period of time, even with the employment of state-of-art forecasting technologies. The precise connection between these sudden changes and specific TC structure remains unclear. Here, we delve into the relationship between TC asymmetry (TCA) of outer-core size and anomalous motion, using best-track data spanning the period from 2001 to 2022. Results indicate that TCs characterized by lower TCA tend to display more pronounced deflections than their normal motion. Furthermore, fast-moving TCs exhibit heightened asymmetry and a propensity to accelerate, whereas slow-moving ones lean towards greater symmetry. In addition, TCs demonstrating substantial angular deviations are more prevalent at lower speeds, while fast-moving ones rarely generate anomalous deflections. These findings provide valuable insights into the potential impact of TCA on anomalous TC motion, which can ultimately be used to enhance the accuracy of TC track forecasting.