Diagnostic study of a rapidly developing cyclone in spring

A diagnostic study of a spring cyclone that developed rapidly was made. This type of cyclone is very similar to a Bomb in North America. The weather caused by the cyclone was severe, and violent wind, tornadoes, hailstorms, and heavy rain were observed. The results show that the occurrence and development of this kind of cyclone are related to the interaction between cumulus convection and synoptic-scale system in a large-scale course of baroclinic instability. It is found that small-scale cumulus frequently merges to form mesoscale systems and that the instability of CISK plays an important role in the release of condensation of latent heating. Conversely, the subtropical jet is very strong, and the coupling between low and upper level jets is found to be different from that studied previously. It is emphasized that the rapid northeastward movement of the cyclone is caused by its asymmetric structure, which favors the collection of cloud droplets to form raindrops, and promotes the occurrence of heavy rain.