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The science
Burgers vortex. A steady axisymmetric vortex balanced between viscous diffusion and inflow stretching has radial inflow u_r = -a r / 2, axial flow u_z = a z and swirl:
v_theta(r) = Gamma / (2 pi r) (1 - exp(-r2/rc2)), rc2 = 4 nu / a
The swirl peaks at r = 1.1209 rc with v_max = 0.6376 Gamma/(2 pi rc), and far away it matches the irrotational vortex of circulation Gamma.
Rankine vortex. A simpler model uses solid-body rotation inside rc (v = v_max r/rc) and v = v_max rc/r outside. Its central pressure drop is exactly rho v_max2.
Pressure. Near the axis the radial momentum balance is cyclostrophic, dp/dr = rho v_theta2 / r, so the pressure deficit is the integral of that from r to infinity. This is why windows and roofs see a large suction.
Debris. A particle obeys dv/dt = (u - v)/tau. Tracers have tau = 0 and follow the air; inertial particles cannot follow the curved path and drift outward, with a Stokes number tau v_max / rc controlling how strongly.
Simplifications. Two-dimensional top view, no ground boundary layer, no turbulence, no translation of the storm, constant air density, debris does not feed back on the flow. The EF class is read from the peak wind only and is a rough guide to the damage scale.