B. Cyclonic circulation is developed. C. Occluded front is fully developed. D. Cyclone dissipates. CES1708 Distribution of clouds associated with an idealized middle-latitude cyclone. Idealized diagram depicting the support that divergence and convergence aloft provide to cyclonic and anticyclonic circulation at the surface.
Divergence aloft initiates upward air movement, reduced surface pressure, and cyclonic flow.
On the other hand, convergence along the jet stream results in general subsidence of the air column, increased surface pressure, and anticyclonic surface winds. CES1712 Average number of days per year with thunderstorms. Because of its close proximity to the source region for warm, humid, and unstable air masses, the Gulf Coast receives much of its precipitation from thunderstorms. CES1714 Stages in the development of a thunderstorm. During the cumulus stage, strong updrafts act to build the storm.