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layers have a large effect on cloud development and the cloud top cannot be given simply by the classical parcel method. In general, the winds were weak. The flow was southerly below 1800 m and northeasterly above 3000 m. The wind shear up to 5 km was mainly from the north and was strongest at around 600 and 3000 m. The synoptic situation on this day is characterized by the approach and passage of a ridge axis of an easterly wave at 700 mb over the center of the GATE A/B-sca1e network (Thompson et al., 1979). The temperature and dew-point indi- cate undisturbed conditions as objectively classified by Ja1ickee and Rope1ewski (1979). Consequently, the average rainfall rates over the GATE A/B-sca1e array estimated from radar rainfall measurements wlere weak (Frank, 1979). The general characteristics of shallow and deep convection on day 261 are described in detail by Warner et a1. (1979, 1980). Within the area surveyed by the Quadra radar sma11-to-moderate sized cumulus clouds developed in a southerly monsoon flow toward an active cloud cluster in the northeast (Warner et a1., 1979). The cloud cluster, however, did not enter into the domain of analysis until after the time period modeled by Turpeinen and Yau (1981). 3.1.1.1.2 Maritime (mixed phase) A. GATE 214 - August 2, 1974 On August 2, 1974 an isolated small cumulonimbus cloud system was observed during GATE. This cloud was well documented by the UK C-130 aircraft which penetrated repeatedly at four levels from 3.2 to 6 km MSL. Excellent wind and momentum flux information is available for this case in which a line of weak cumulonimbus clouds formed over the tropical ocean. This case was selected because it represented a reasonably well doclJmented maritime mixed phase convec- tive cloud which is currently under study by a number of scientists; and a com- parable closed case exists. This case is described by Lemone et a1. (1984) and in other GATE reports. B. HIPLEX - July 3, 1979 The July 3, 1979 case was selected because it provides an excellent opportunity to examine the microphysical and dynamic evo"lution of natural and seeded clouds. Early in the day, a dry1ine extended from thl~ Texas Panhandle through southeastern New Mexico, to the west of the project area, and on to the south. During the day the dry1ine moved eastward and combined with the instability pro- duced by an upper-level disturbance to generate a line of convective activity by 1 ate afternoon. The thunderstorms moved rather slowly across the western port ion of the project area as the line extended more than one hundred miles in a NNE to SSW orientation. The seven-station upper air network was operational from 1500 through 0300 GMT, with only one missed sounding. Five of the :~5 automatic surface weather sta- tions were inoperative, but the others produced nearly complete data sets. The recording raingage network was operational, as was the SWR-75 weather radar and satellite laserfax equipment. 11.