Preliminary Damage Patterns from Drone footage over a Heavily Forested Areas in Southern Illinois from an EF4 Tornado (229)

Patrick Spoden, National Weather Service, Paducah, Kentucky

Debbie Newman, Illinois Nature Preserves Commission

 

Abstract:

On 1 March 2017, a tornado producing EF4 damage moved across southeast Missouri and southern Illinois. A week after the initial damage survey, a request came into the National Weather Service Office in Paducah to figure out what happened in the heavily forested area near Ava, Illinois. Walking through the forested area, which was 80-90% destroyed (50% uprooted and 50% snapped), it became apparent that it was likely multiple vortex during that time frame. Other damage surveys associated with this tornado revealed a multi-vortex structure. Due to the large number of trees and topography, it was difficult to determine exactly what happened from the ground. Some of the trees were estimated to be 140 years old and 50-60 ft tall.

The owner of the property was able to secure a drone, which flew over the area on 31 March 2017 and again in July 2017. This presentation will focus on the different damage patterns as seen from the drone. The high quality of the data allowed a determination that the bottom layer of trees were all blown in a westerly direction, while the top layer indicated a well-defined convergent pattern through the property. This may suggest the one vortex never directly crossed the property, while the other vortex likely moved on a west to east path through the center of the property.