A new parametric tropical cyclone wind-profile model: Testing and verification

A new parametric vortex model with radial profiles of evolving tangential winds in tropical cyclones is presented. The model employs five key parameters: (a) maximum tangential wind, (b) radius of maximum winds (RMW), (c) curvature growth that increases tangential wind with increasing radial distance from the vortex center inside the eye (d) decay that decreases the wind with the distance from the center outside the eye, and (e) radial width that controls the width of the eyewall wind maximum. The last three parameters do not change the magnitude at the RMW.

Tangential wind data from hurricane reconnaissance aircraft were used to test and verify the vortex wind-profile model. A minimization technique, via the Levenberg-Marquardt optimization method, was used to fit the data to the model gradient wind profiles in different stages of tropical cyclones that range from tropical storms having nearly flat wind profiles to hurricanes exhibiting sharp single-maximum and dual-maximum wind profiles. Comparisons of the fitted and observed profiles of relative gradient wind, absolute vorticity and angular momentum show excellent agreements.