Comparison of the VORTRAC retrieved structure of Hurricane Danny (1997) to prior analyses

Tropical cyclone (TC) intensity forecasts continue to be one of the most challenging aspects of hurricane prediction. However, through an innovative new tracking and analysis tool, a high resolution, real-time analysis and greater understanding of the complex dynamics of TCs is possible, both leading to better forecasting skill. The validity of this tool was analyzed in this research.

Through the ground-based Velocity Track Display (GBVTD) technique, a single ground-based Doppler radar data can be used to retrieve the three-dimensional (3-D) kinematic structure of a TC. The GBVTD technique and GBVTD-simplex center finding algorithm formed the basis of the Vortex Objective Radar Tracking and Circulation (VORTRAC) software package for this purpose. VORTRAC is capable of automatic center tracking and retrieval of storm-scale circulation, structure, and central pressure tendency of a TC, for use in real-time forecasting and research. VORTRAC was utilized to analyze Hurricane Danny (1997). This analysis was then compared to the National Hurricane Center (NHC) best track (considered to be the “ground truth”) and the manual GBVTD analysis previously performed on Danny. Additionally, the VORTRAC runs from two separate radars were compared.

The VORTRAC software package was shown to be a viable tool for the retrieval of the detailed 3-D structure of a TC. VORTRAC was shown to agree well with observations and with manual GBVTD analyses, while efficiently processing data at a high temporal resolution. This promises to be a useful tool for both forecasting and research.