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. . . Dr. Flueck also performed some radar statistical studies for SCPP-l events from data accumulated from the 1979, 1980, 1982, and 1983 operational years. Table 2.3 provides the dates, seed decision and microphysical category of the data. There were seven seeded and seven not seeded events selected. Table 2.4 contains statistics for all the cases in Table 2.3. The parameters tested in Table 2.3 include the size of the 10 dBz echo, the size of the 30 dBz echo, and the maximum dBz level. Values were averaged and significant levels were t~sted with the Mann Whitney and F tests. Other than the initial values for the seeded cases being larger than the not seeded cases there appeared to be little detectable E~ffect of the seeding. Table 2.5 provides similar information to that of Table 2.4 except the data is limited to the A and B microphysical classifications only. Sample sizes are quite small (6 not seeded and 3 seeded) so inferences are quite tentative. Data in Table 2.5 would tend to indicate a lower dBz level in the seeded cases. Investigations of seeding signatures in radar data can be rather complicated due to the dependence of the radar intensity upon the diameter to the sixth power relationship. If seeding were to produce more smaller particles than in natural conditions then the radar reflectivity in seeded storms would actually be expected to decrease. Figures 2.5 and 2.6 display the information in Table 2.4 and 2.5 for the size of the 10 dBz reflectivity. . . . . . 2.3 Guidecell Conversion. . NAWC worked with Bureau employees in Auburn to place Guidecell 3, a computer model developed by NAWC, on the Bureau's PDP- 1103 located in Auburn. NAWC's programmer utilized a similar computer in Salt Lake City to debug the converted . 2-9 .