While many tornadoes feature a single, towering funnel cloud, some exhibit unique characteristics. One such phenomenon, known colloquially as the “dead man walking” tornado, is notable for its distinctive appearance and the significant impact it can have on affected areas.
Defining This Unique Tornado
The “dead man walking” tornado is a specific manifestation of a multi-vortex tornado. It features multiple smaller funnels, or sub-vortices, rotating within a larger, overarching tornado. This configuration creates an eerie, humanoid appearance, resembling a giant figure with multiple “legs” moving across the landscape. The nickname gained prominence following the 1997 Jarrell, Texas tornado, which exhibited this unique visual characteristic. The perception of a walking figure is sometimes attributed to pareidolia, where the human brain identifies familiar patterns in random stimuli. These tornadoes often appear large and can give the impression of being slow-moving, contributing to their unsettling visual.
How This Tornado Forms
The formation of a “dead man walking” tornado, like other powerful tornadoes, begins within severe supercell thunderstorms. These storms are characterized by a deep, persistent, rotating updraft known as a mesocyclone. The specific conditions leading to the multi-vortex structure involve particular atmospheric dynamics. For instance, the 1997 Jarrell tornado formed despite weak upper-level winds and minimal wind shear, driven by extreme atmospheric instability with high Convective Available Potential Energy (CAPE) values.
Within the main vortex, smaller sub-vortices can form and swirl around the central axis. These sub-vortices are responsible for the “legs” that give the tornado its name. The ground contact point of the primary vortex may also exhibit a “wandering” motion, enhancing the illusion of a walking entity. These tornadoes can also exhibit an unusually slow forward speed, sometimes moving at only a few miles per hour, which is atypical for most tornadoes.
Observing and Understanding Its Danger
Observing a “dead man walking” tornado presents significant dangers. Its slow forward speed, which can be as low as 5 to 10 miles per hour, is deceptively dangerous. This slow movement can create a false sense of security, leading observers to believe they have more time to seek shelter than is actually available. Unlike faster-moving tornadoes that quickly pass over an area, these systems can remain over one location for several minutes, subjecting it to prolonged and extreme wind speeds. For example, the 1997 Jarrell tornado remained over the Double Creek Estates subdivision for approximately three minutes, delivering continuous winds exceeding 260 miles per hour.
This prolonged exposure to intense winds leads to catastrophic damage, often grinding structures to their foundations. The multi-vortex nature also creates uneven and unpredictable damage patterns. The large size of these tornadoes can make them difficult to distinguish from typical storm clouds, leading some to mistake them for less threatening weather phenomena. The devastating real-world implications of these tornadoes are evident in events like the Jarrell tornado, which resulted in 27 fatalities and significant property destruction. Such tornadoes can also cause extensive animal fatalities, with some instances reporting hundreds of cattle dismembered or skinned.