What is a Mesoanticyclone?
A mesoanticyclone is a localized atmospheric system characterized by anticyclonic (clockwise in the Northern Hemisphere, counterclockwise in the Southern Hemisphere) rotation on the mesoscale level. Unlike its counterpart, the mesocyclone, which is linked to tornado formation and severe storms, a mesoanticyclone is often associated with subsidence and more stable atmospheric conditions.
Mesoanticyclones can develop within certain types of storm systems, including supercells. While mesocyclones typically form in an environment with strong wind shear that supports rising air and storm intensification, mesoanticyclones occur in regions where descending air dominates. This process can lead to clearing skies or weakening storm activity.
Though mesoanticyclones are not typically dangerous, they can still influence local weather. For example, they may suppress thunderstorm development or create regions of enhanced wind flow. In rare cases, they can contribute to the formation of anticyclonic tornadoes, which rotate in the opposite direction of typical tornadoes.
Understanding mesoanticyclones is crucial for meteorologists when analyzing storm dynamics, as they can impact storm intensity, longevity, and movement. While they are less studied than mesocyclones, recognizing their presence helps refine weather predictions, particularly in severe weather outbreaks.