is also observed in [@belik14], which revisits Serrin’s “swirling vortex” model [@serrin] and investigates solutions to the Navier–Stokes and Euler equations in spherical coordinates with the velocity, $\bf v$, satisfying the power law $|{\bf v}|\propto r^{-\alpha}$, where $r$ is the distance from the vertical coordinate axis and $\alpha$ is not necessarily equal to $1$. The streamlines and other physical quantities of the modeled vortices, such as isobars, exhibit self-similarity.

Geometric self-similarity in tornadoes manifesting itself over several scales is not a new concept [@church77]. Figure \[fig:hier-vort\], taken from [@church77], illustrates a hierarchy of known vortex scales in tornadic supercells. Phenomena occurring at all of these scales may not be easy to observe, but videos of recent large tornadoes show subvortices of subvortices within tornadoes [@wadena10; @elrenovideo13]. These sub-subvortices, called suction vortices or suction spots, are short lived and very intense, and their existence is often confirmed by studying the track of a tornado afterwards. See Figure \[fig:suctionspots\] for examples of such evidence [@fujita81].

Some observed tracks left by the suction vortices within a tornado are as narrow as $30$ cm. Some of these paths appear to originate outside the tornado and intensify as they move into the tornado. We identify 