The science
The flow is a Burgers vortex: tangential wind v(r) = (Gamma / 2 pi r)(1 - exp(-r^2 / r_c^2)) with radial inflow v_r = -a r. Its peak is 0.63817 Gamma / (2 pi r_c) at r = 1.1209 r_c. Away from the ground, pressure follows cyclostrophic balance
dp/dr = rho v^2 / r, p(0) - p(inf) = -rho (Gamma / 2 pi r_c)^2 ln 2
The wind-speed classes are only the 3-second-gust thresholds of the Enhanced Fujita scale (EF0 65 mph ... EF5 200 mph). The real EF rating comes from damage surveys, so the label here is a speed class and not a damage rating.
Honest simplifications: the vortex is axisymmetric and steady, friction at the ground, sub-vortices, debris loading and the funnel's vertical structure are ignored, and the pressure integral neglects the radial-inflow term. Checks: peak wind and radius by scan, the closed-form ln 2 pressure drop, and a tracer completing one predicted lap.