cyclones the tangential component of the velocity, $v$, exhibits decay proportional to $r^{-\alpha}$ with $0<\alpha<1$, where $r$ is the radial distance from the center of the cyclone [@mallenmontgomerywang2005], it has been only much more recently that similar power laws have been observed for the tangential component of the velocity in tornadoes [@wurmangill00; @wurman02; @wurmanalexander05; @kosibatrappwurman08]. Such power laws could perhaps have been anticipated based on the results obtained earlier in a vortex simulator [@lund-snow93], in which a power law of the form $r^{-0.63}$ has been found for a much smaller physical scale and very different Reynolds number. In fact, recent theoretical results suggest that power laws with similar exponents hold across a whole range of scales, ranging from a bathtub vortex, through dust devils and firewhirls, to tornadoes and tropical cyclones [@klimenko14].

We now briefly review some of the observations made by Wurman and his collaborators based on mobile Doppler radar data analyses [@wurmangill00; @wurman02; @wurmanalexander05; @kosibatrappwurman08]. In these papers, the tangential winds outside the tornado core roughly fit the [*modified Rankine*]{} vortex model, in which the core is modeled as a solid-core rotation with the mean tangential velocity depending linearly on radius (i.e., $v\propto r$) and outside of it 