Precipitation development in some cumulus congestus as a function of the environmental conditions in CCOPE

Abstract

Radar and direct aircraft measurements are used to characterize the precipitation development up to the mature stage at the high levels of some long-lived cumulus congestus and to estimate the precipitation efficiency at their cloud base The observations at about the -12ºC level are studied as a function of the overall particle growth environment and of the atmospheric conditions. The results indicated that the concentration of ice particles or alternatively the maximum attained reflectivity are sensitive functions of the cloud lifetime and correlate positively with the atmospheric static energy. Precipitation efficiency was estimated from 0 to 30% for these clouds. Contrary to the well known findings for large storms the clouds studied have no apparent influence from the vertical wind structure.