The Athenium Analytics Historic Tornado Geometries resolve two-dimensional damage swaths from all confirmed tornadoes that occurred in the continental United States between 1995 and 2019. These are organized into 25 hosted feature layers, each having geometries for all confirmed tornadoes available from the NOAA SPC SVRGIS dataset.
Tornado damage swaths were constructed from the NOAA SPC SVRGIS starting and ending points, with storm motion vectors used to determine any missing ending points. For tornadoes with mapped survey damage swaths available, either from past publications or the NOAA Damage Assessment Toolkit, refined swaths including these shapes are provided. Damage is defined by intensity at Enhanced Fujita Scale level. For tornadoes without full EF-scale level information, an idealized tornadic vortex was used to determine the maximum level of intensity along the swath.
Each intensity level for each tornado is given as its own multipolygon, organized by the peril_id term. Exact start and ending times to the hour of tornado occurrence are also provided as a field, with tornadoes occurring on the same Julian date (from 1200 UTC - 1200 UTC) grouped by the event_id descriptor.
The test data shows all 2D tornado geometries for the year of 2019. If further years are desired, please contact email@example.com for additional licensing terms.