Comparisons of Close-Range Radar Observations with UAS-Based Damage Analysis of the 11 May 2023 Cole OK Tornado

On 11 May 2023 an EF-1 tornado tracked through the rural areas of Cole OK affecting predominantly farmland and open fields. This tornado was studied through close-range rapid-scan Doppler radar (PX-1000), terrestrial photography, UAS visible (3 cm spatial resolution) and multispectral (8 cm spatial resolution) imagery, and high-resolution satellite (PlanetLabs Skysat 50 cm spatial resolution) imagery. UAS and satellite data are used to augment interpretation of the details of the evolution in Doppler velocity data, including cyclic periods of weakening and intensification. Although the vortex appeared to be weak in mobile Doppler radar data, UAS imagery revealed heavy damage to a field of young corn including cycloidal marks. Additionally, in an area with little vegetative damage, video shows the roof from a newer frame home was partially removed and ejected upward, possibly indicating relatively weak tangential flow and relatively strong upward flow. The tornado path width was considerably narrower than suggested by radar data at approximately 12 km range as documented in UAS imagery. One complication of damage pattern analysis involved the occurrence of the previous 19 April 2023 EF-3 Cole OK tornado on a path about a mile to the northwest, as well as an anticyclonic tornado with that storm southeast of the track analyzed here. This study highlights the need to develop damage indicators more reflective of tornado intensity in rural areas and better understand the role of land cover in tornado behavior.