Where Have the EF5s Gone? A Closer Look at the "Drought" of the Most Violent Tornadoes in the United States
Où sont passées les tornades de catégorie EF5 (échelle de Fujita améliorée 5) ? Analyse approfondie de la « disette » des tornades les plus violentes aux États-Unis
Lyza, Anthony W. ; Brooks, Harold E. ; Krocak, Makenzie J.
Année de publication
2025
As of January 2025, the United States has gone over 11 years without the occurrence of a tornado rated enhanced Fujita 5 scale (EF5) on the EF scale, constituting the longest "drought" in F5/EF5-rated tornadoes since the beginning of official records (1950). This article places the drought of 5-rated tornadoes in the context of a long-term tornado climatology. A key breakpoint exists between how the legacy F scale and the EF scale handle the complete destruction and sweeping away of single-family homes, with standard "well-constructed" homes being swept away constituting F5 damage on the F scale but only EF4 damage on the EF scale. To illustrate this point, adjusting the lower bound of EF5 on the EF scale from 201 to 190 mph or increasing all from 190-200-mph EF4s to >200-mph EF5s to account for this breakpoint in the handling of single-family homes would lead to consistent 5-level rating assignments from 1880 to the present day. Furthermore, contextual evidence that was used to aid in identifying 5-level damage in the F-scale and early EF-scale eras could assist in identifying top-tier intensity tornadoes. These findings ultimately lead to questions regarding what the highest possible rating of a tornado should represent from both physical and societal perspectives.</div>
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