Analysis of Extratropical Cyclone Circulation Centroids using Ultra-High-Resolution 3D Radar Wind Fields in the Seoul Metropolitan Area

Extratropical cyclones, meso- to synoptic-scale atmospheric vortices, are characterized by rising, converging air masses, are associated with low-pressure systems and frontal boundaries, frequently causing substantial damage through intense winds and heavy precipitation. Traditional monitoring approaches utilizing radar reflectivity encounter significant limitations when addressing spatial shifting or regional variations in precipitation. To overcome these challenges, we propose a novel technique for tracking extratropical cyclones through the detection of cyclonic circulation centroid from radar wind fields using a multi-parameter analysis.
This method employs high-resolution 3D wind data from the Korea Meteorological Administration's radar network, processed through the “WInd Synthesis System using Doppler Measurements (WISSDOM)”, which provides comprehensive wind data across multiple altitudes, facilitating 3D characterization of precipitation system dynamics (Liou et al. 2012, Kim et al. 2018). We objectively identify cyclonic rotation centers by analyzing wind direction, speed, and vorticity from WISSDOM. When applied to 50 extratropical cyclone cases during 2023-2024, this technique successfully detected centers in 46 cases (92% success rate) (Park et al. 2025). 
In this study, we applied this advanced technique to the Seoul Metropolitan area using ultra-high-resolution radar wind fields specifically designed for densely populated urban environments. We generated these enhanced wind fields by improving the spatial resolution of WISSDOM wind data. Our three-step approach includes: 1) identification of potential cyclonic centers based on wind velocity and vorticity analysis, 2) examination of cyclonic vorticity areas through wind direction patterns analysis, and 3) determination of the optimal cyclonic center location. The analysis of vertical structure within these systems through our method enables the identification of developmental stages and intensity variations, as well as the temporal tracking of cyclone movement trajectories. This research substantially advanced our understanding and predictive capabilities for extratropical cyclones and associated severe weather phenomena. The technique also demonstrated significant potential for extension to tropical cyclone and mesocyclone centroids detection, facilitating enhanced early warning system for torrential rainfall events.

Acknowledgements:
This research was supported by “Development of radar based severe weather monitoring technology (KMA2021-03121)” of “Development of integrated application technology for Korea weather radar” project funded by the Weather Radar Center, Korea Meteorological Administration.

Keywords:
Cyclonic Circulation, Extratropical Cyclone, 3D Doppler radar wind field, WISSDOM, Weather Radar Network