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only 1.5/l in a downdraft on the southeastern or eroded edge of the cloud. The Lear still measured an updraft exceeding 10 m/s in the core on the northwest side of this cloud. On the pass following seeding, the King Air aircraft encountered a well- defined ice crystal plume. The 2DC recorded a peak concentration of 440/l, and the 1DC concentration exceeded 1000/l in the core of the ice crystal plume. The ice crystal plume extended over a distance of about 350 m at this time, which y/as approximately 2 min after we estimate that the dry ice pellets should have fallen through this alt"itude. The ice crystal plume at this time was thus very narrow, and contained concentrations far higher than was the target for the experiment. Such a curtain of ice crystals would have to spread to sizes of more than 10 km before the concentration would be diluted to near the target concentration of lOll. It thus appears that the seeding produced concentrations much higher than the target con- centration in this case. The precipitation particles encountered on the 11 min pass were large in com- parison to those seen early in the lifetime of other HIPlEX-1 clouds. The pro- duction, via accretional growth, of 4-5 mm !~raupel only 11-12 min after seeding would require liquid water contents higher than 2.5 g/m3 (Cooper, 1982), much larger than the value of about 1 g/m3 that \'Ias observed. The Lear also, on its passes near cloud top, never found liquid water contents of more than about 0.5 g/m3. Only through other processes (such as combined aggregation and accretion) could these sizes be reached in the available time. There is some evidence that this precipitation should be associated with seeding; however, aggregation may have played a role in its development. The estimated rainfall from this case, was 9.4 mm/km, the highest of any HIPlEX-1 cloud. The rainshaft was clearly identified on the King Air radar, and the mapping passes at the +10 oC level were flown through the core of that echo. The drop size spectra is close to exponentiiil, with an extrapolated intercept of about 1 x 106 vs the expected value of 8 x 106 for a Marshall-Palmer distribu- tion. A line of intense thunderstorms extended to the south from the location of this cloud, and general conditions were evidently favorable for development in this area. In fact, the conditions on the initial pass exceeded those designed to avoid intense convective developments: the average updraft exceeded 10 m/s and the buoyancy exceeded 1 oC. In summary, seeding produced a clear ice siqnature. The time to first echo was very short, but appeared associated with natural precipitation develop- ment. Rainfall ranked easily at the top in the experiment. This resulted from a relatively high rainfall rate which persisted over the entire mapping period. Factors possibly contributing to the intensity of the pre- cipitation from this case are: (a) strong positive buoyancy and updraft at the time of seeding which carried the ice cl~ystals to the -20 C level and which maintained the supercooled water content of the cloud; (b) seeding, which produced a high concentration of precipitation particles in this case; and (c) low wind shear which enabled the precipitation embryos to fall through the supercooled cloud. Precip"itation development appeared to proceed via accretional growth to graupel in this case. 14.