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I I I 'I I I I I I I I I I I I I I I I Of the six active seed cases, four were interpreted as having some potential for dynamic seedability. The measured physical responses to seeding were in general agreement with the stated physical hypothesis; i. e. increased vertical growth of the cloud tops in correlation with the time and location of the glaciation generated by the seeding event, and the prolonged growth of precipitation and the subsequent prolonged fallout pattern. The other two active seed cases were interpreted to have questionable dynamic seedability. One due to stable air near the cloud base resulting in weak updrafts aloft. The artificial glaciation was not sufficient to increase the buoyancy significantly. In the other case, there was an intense mid-level inversion which was significantly limiting the vertical growth of the clouds. Again, the artificial glacia- tion was too weak to accelerate the updraft beyond the inversion level. We conclude that the warm rain process is usually active in the initiation of showers in this area. . Cloud bases are warm (+150 to +180C) and thus a cloud depth of 10,000-12, 000 feet allows for the generation of precipitation size particles through condensation - coalescence. There appears to be a high frequency of mid-level stable layers that limit the vertical growth of clouds on many shower days. These layers are typical at the _50 to -100C levels. Thus the ice phase pro- cess is generally weak except for the larger cells which can accelerate beyond the mid-level stable layers. We further conclude that there is a relatively high frequency of days with dynamic seedability (30-50 days). This season's analysis supports the findings of Simpson et al (1978) regarding the climatologi- cal frequency of potentially seedable days. Thus, in summary, we feel that the May-August season has been 123 ---.-