An Automated Tornado Damage Assessment Model: Providing Rapid Situational Awareness to the Federal Emergency Management Agency (FEMA)

A considerable challenge faced by the emergency management community at the start of a large-scale natural disaster is gaining situational awareness to begin response and recovery planning. Tornadoes are one of the most common natural disasters inherent to North America, with an average of over 1,000 occurring per year in the United States(1). While only 5% of these tornadoes are categorized as violent (rated EF3 or above), a single tornado path can continue on for tens of miles, causing severe damage to populations, structures and entire communities in its wake(2). For three historic and catastrophic tornadic events (Joplin, MO 2011; Alabama 2011; Moore, OK 2013), preliminary damage assessments derived from aerial optical imagery took over 5 days to complete, causing prolonged delay for the US Federal Emergency Management Agency (FEMA) to gain situational awareness needed for decision support. Here, we test a GIS-based tornado damage assessment model that incorporates US parcel data, the National Weather Service’s (NWS) Damage Assessment Tool (DAT) tornado path polygons and damage functions based on the Enhanced Fujita (EF) scale damage indicators used by the National Oceanic and Atmospheric Administration (NOAA) to rate tornadoes according to structural impacts. The model is tested for the three previously mentioned case studies, resulting in 81-90% accuracy when the output damage assessments are compared to those derived manually from aerial optical imagery and field surveys. This GIS-based model could provide emergency responders an opportunity to cut lead time for preliminary damage assessments and improved situational awareness from 5 days down to 24-72 hours. This presentation will describe the methodology behind the model, examine results from the 3 case studies, and discuss the significance of using this model for tornadoes that occur in the future.

(1) https://www.ncdc.noaa.gov/climate-information/extreme-events/us-tornado-climatology
(2) https://stormaware.mo.gov/tornado-facts-history