Wind Radii Climatology of North Atlantic Tropical Storms and Hurricanes

Tropical cyclones (TCs) bring numerous hazards such as high wind speeds, storm surge, rainfall- induced flooding, rip currents and tornadoes. In efforts to protect life and property and to better understand these potentially dangerous systems, numerous studies have investigated TC track and intensity forecasting and climatology. However, fewer studies have focused on the climatology of TC sizes, which are strongly correlated to the various TC hazards. This project analyzes the wind radii climatology of TCs in the North Atlantic basin in an effort to help understand more about TC structure and to aid in communication of this often overlooked parameter.

To obtain wind radii climatology, HURDAT2 data from 2004 to 2022 was utilized. The data was separated into three geographical bins (south of 20N, 20N-30N, and above 30N), then stratified by intensity (50-60 kt, 65-95kt, 100+ kt). The mean, median, standard deviation and histograms were computed for each wind radii threshold and quadrant. This method was repeated excluding all zeros from the dataset, and for aircraft reconnaissance data only. Results showed that wind radii are strongly correlated with latitude.

Cumulative distributions of tropical cyclone wind radii were also calculated to compare previous landfalling tropical cyclones to climatology. Hurricane Sandy was in the 99th percentile, Charley in the 8th percentile, and Ian in the 61st percentile. With a strong connection between TC size and risks to the public, understanding the size of a storm before landfall can significantly increase awareness of hazards and aid in emergency management decision making for affected regions.