In Situ Video Observations and Analysis of the 16 June 2014 Pilger, Nebraska EF4 west Tornado

Abstract

An unusual tornado event involving two large and violent EF4 tornadoes occurring simultaneously impacted the Pilger, NE area on 16 June 2014, resulting in two deaths. A privately funded scientific field campaign successfully obtained in-situ video observations inside the western-most tornado prior to it striking the town of Pilger. The results resolve fine details of the tornado core wind field, which are presented and discussed, including several important or unique observations not previously documented within existing in-situ tornado video research. These include documentation of many sub-vortices (as many as nine concurrently at one point) evolving and dissolving on the order of seconds or fractions of seconds while rotating about a concentrical axis. Visual observation of a single but separate vortex that was likely a sub-vortex on the outside rim of the tornado core and observations confirm tornadic damage well outside the visible parent tornado vortex. This study also adds to the small number of tornado cases documented using in-situ observations as a reference for further research.