Abstract
The intimate relation between the activity of the cumulus convections and the mesoscale convergence fie'd is studied over the coastal area of the Japan Sea on January 19, 1965 by using the data of the “Heavy Snow Storm Research Project” which includes the aerial photographic cloud observation and maritime observation in addition to the radar, aerologi-cal and surface observations,
The remarkable fact is that the activity of the cumulus is strongly controlled by the mesoscale convergence field, i.e. the well-developed cumuli exist only in the area of con-vergence of more than 10-4sec-1.
The roles of the cumulus convection are discussed concerning the dynamical balance of the mesoscale disturbance and mixing effects on the momentum and heat distribution.
