The dynamical response of the hurricane wind field to rainband heating

We present a method to understand the dynamical impact of diabatic heating in rainband convection on the tropical cyclone wind field. This method uses the linear but fully nonhydrostatic model of vortex dynamics, now known as 3DVPAS. The model can simulate the time-evolving asymmetric and symmetric responses of a balanced, baroclinic vortex to the diabatic heating which may rotate around the center of the vortex. The structure of the diabatic heating is designed in accordance with radar observations of spiral rainbands. Common features of the wind field around spiral rainbands are recovered, such as a shallow overturning secondary circulation and an accelerated tangential flow along the outward side of the rainband. A procedure is introduced to isolate the impact of spiral rainbands on the surrounding hurricane wind field in high resolution, full-physics simulations. Some possible implications for the secondary eyewall formation are discussed.