note: I assigned this to tropical cyclone genesis but it pertains more to generation of mesovortices which often serve as seeds for tropical cyclone genesis, so you may reclassify depending on how it fits with other talks.
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Generation of long-lived mesoscale warm-core vortices resembling mesoconvective vortices was investigated with a nonhydrostatic mesoscale model (nested inside a large outer domain to contain the full mass circulation). A large variety of specified heating distributions were used, including ring and linear ensembles of cloud-scale heating, and a broad region of cooling resembling the effect of MCC anvil melting. Some experiments were conducted with ambient initial cyclonic rotation and ambient initial anticyclonic rotation. One experiment applied a heating pattern inside a vortex left over from previous heating. The experimental design prohibits Rossby radius reduction from reduced Brunt-Vaisala frequency. Instead, the Rossby radius was found to be reduced through equivalent depth reductions as important adjustment is associated with the outward propagating internal waves.
Vortices are found to be generated through a variety of processes in the different experiments. Cooling and heating both are capable of generating good vortices. Ensembles, even in a finite line arrangement, produce a collective circulation integral effect surrounding their small-scale vortices. With strong flow through the heating functions, parcels detraining prematurely because of lateral flow-through provide a major source of vorticity to the mesoscale environment, implicating possible importance of cloud detrainment resulting from cloud-relative flow.
Potential vorticity generation diagnostics are evaluated and have been examined in detail for some experiments. The baroclinic warm-core shear (horizontal component of vorticity) in a convective vortex results in potential vorticity generation at small radius and potential vorticity reduction at large radius when heating occurs inside (along a ring, not at the center of) the old vortex. This mechanism offers an explanation for how mesovortices left over from previous convective systems can aid tropical cyclone genesis.
Experiments with sufficient heating are able to spin up a surface vortex to hurricane strength, though the dynamics unlikely to be those operating in natural hurricanes. However, it is interesting that line heating can result in balling up of a line vortex to produce a compact circular vortex. Also, when the diabatic heating is allowed to become proportional to vertical motion (in 3 dimensions, not wave-CISK) and excessive unnatural vortex deepening occurs, spiral patterns appear and diabatic heating occurs around but not inside the circulation centers.