Large Eddy Simulation of an Entire Tropical Cyclone From Initial Vortex to Maturity

We simulated a tropical cyclone in an idealized environment, from its weak initial vortex to maturity, using a regional numerical weather prediction model with a uniform horizontal resolution of 100 m, regarded as a large eddy simulation (LES). Results of the LES were compared with those of the same model, but with a horizontal resolution of 2 km. Both experiments attained similar peak intensities ((Formula presented.) hPa), but the LES uniquely captured kilometer-scale rolls in the boundary layer, persistent shallow mesovortices near the eyewall, and countless sub-kilometer-scale patches of positive and negative vorticity. Rapid intensification (RI) in the LES was delayed by approximately 26 hr relative to that in the 2 km model. Composite analysis confirmed that mesovortices interfered with the azimuthally averaged secondary circulation. The prevalence of negative vorticity and decelerated inflow in the LES are likely to delay the RI.