Characterizing Tornadic Convective Features in Tropical Cyclones using TCTOR-RF

This study aims to utilize radar observations to characterize tornado-producing systems within tropical cyclones by integrating the radar-defined Tornadic Convective Features (TCFs) with the International Best Track Archive for Climate Stewardship (IBTrACS) dataset between 2017-2023. The TCTOR-RF (Tropical Cyclone Tornado Records + Radar Features) dataset builds on top of the TCTOR dataset (Edwards 2010) by including these radar-defined TCFs with the tornado records. TCFs are defined by grouping contiguous areas with composite radar reflectivity values greater than 40 dBZ from the Multi-Radar Multi Sensor product (MRMS) with ground-based tornado reports from the National Storm Prediction Center. The radar-defined properties including the size, depth, morphology, and convective intensity of the TCFs are summarized. The TCFs are then temporally and spatially collocated with tropical cyclones in the IBTrACS dataset. In total, TCTOR-RF includes 447 tornadoes and their matching radar-defined TCFs collocated with 43 tropical cyclones between 2017 and 2023. The tropical cyclones are categorized based on the Saffir-Simpson Scale, while the TCFs are categorized based on the Enhanced Fujita (EF) Scale. 90% of all the tornadoes within TCTOR-RF are EF0’s and EF1’s and 62% of the tornadoes occur in the northeast quadrant of the tropical cyclone relative to the storm’s center. 48% of the tropical cyclones within the dataset are tropical storms. TCFs associated with tropical cyclones are relatively weaker with smaller areas of 40 and 50 dBZ, and lower maximum heights of the 18 dBZ echo top on average than those non-tropical cyclonic TCFs. Unlike the non-tropical cyclonic tornadoes that tend to propagate towards the east in alignment with the TCF orientation, tornadoes from tropical cyclones propagate northwestward aligning more with the counterclockwise rotation of the tropical cyclones, and at slower speeds and exhibit shorter lifespans.