The formation and organization of spiral rainbands in numerically simulated tropical cyclones

The structure of spiral rainbands and their propagation mechanism have been the focus of many previous observational and theoretical studies. However, not many studies examined how spiral rainbands are triggered and organize in the first place. Some of previously proposed mechanisms for the initiation of spiral rainbands include the release of symmetric instability. This study will examine the early evolution of spiral rainbands in numerical simulations of Hurricane Bill (2009). In addition, spiral rainbands in the idealized, no-mean flow simulation of tropical cyclone (e.g., “hurricane-in-a-box”) will be examined and compared to their counterparts in Hurricane Bill (2009) simulations.