Fatalities Associated with Severe Thunderstorms

On average, high wind events have been the 4th leading cause of weather-related deaths for 10 years. This study explores the relationship between storm speed and fatalities associated with severe thunderstorm wind. A thunderstorm is considered severe if it produces winds greater than or equal to 58 mph. Only warned severe thunderstorm events in the United States with at least 1 wind fatality were included. Gibson Ridge 2 Analyst was used to determine the storm speed and direction of fatal severe thunderstorm wind events from 2017-2020 and compared to the forecast speed and direction in the warning associated with the events. 104 events were included in the study, which included 127 fatalities overall. The average forecast speed was calculated at 45 mph. Approximately 52% of all fatal severe thunderstorm wind events collected observed speeds of 45 mph or higher. About 57% of those events observed speeds of the severe thunderstorm criteria of 58 mph or higher. These results indicate faster storms can increase the likelihood of fatalities during severe thunderstorm events. Improvements to event messaging and more location-specific information could aid in the preparedness efforts of National Weather Service partners and the public.