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the lower altitudes, is actually widespread (nearly 100 percent coverage) at the surface. Thereafter the vertical gradient is strong and continues that way through the next day in the second column. The storm arrived earlier at KABR and with a greater intensity (third column) but similar vertical gradient. In the bottom part of the third column, most of the sky becomes echo free, except for the lowest altitudes, which are sampled only close to the radar. It is not known if that pattern represents exceedingly shallow snow or anomalous propagation producing ground clutter reflections during the night hours. Near sunrise (bottom of column 3) and thereafter on the second day (right column) the pattern appears to represent genuine shallow snow observable only close to the radar. At far ranges the radar beam climbs above this shallow snow and fails to accurately indicate the precipitation intensity near the surface. When the SAA is integrated into the WSR-88D baseline, users will be able to change adaptable parameters as conditions change. More study is needed to optimize adaptable parameters for different storm types. 4. ADDITIOr~AL Ze-S DATA SETS 4.1 Anchorage, Alaska In Section 9.5 of Super and Holroyd (1998), we indicated the data set from Alaska was severely limited for the 1996-97 season and could not be analyzed. We inquired at the Anchorage office about more recent data sets. The problems continue. Available gage data are in locations with serious radar blockage. We cannot derive reliable alpha and beta constants for the Anchorage area without installation of a special gage network, which is beyond our scope of work. In addition, not much Level II data has been recorded for Anchorage during winter storms. Therefore, no Ze-S relationship is provided for this important climate zone. 4.2 Seattle, Washington Work with the KA TX, Seattle, Washington, radar data and gages was not completed. Preliminary indications were that the results would be poor. KA TX is at an elevation of only 181 m, which is almost always below the melting level. Consequently, the primary problems (Westrick et aI., 1999) for the SAA are bright band contamination and beam blockage from surrounding higher terrain. Furthermore, there is considerable vertical separation between the lowest unblocked radar beam and the surface where the snow gages are located. Experience indicates that there is appreciable precipitation growth in layers near the surface in winter orographic situations. The radar beam cannot view this growth zone in the Cascades east of Seattle. Therefore it is expected that a very small alpha would result. Table 1.-Basic parameters for the California gages and the NEXRAD radar beam above each Azim. Range Elev. Tilt Carr. Clearance Gage site deg. km m deg. DBZ R2 n Alpha Beta m Brush Creek 46.0 31.9 1085 2.40 0 0.402 29 20.0 2.1 363 De Sabia 359.7 42.2 826 1.45 0 0.122 15 25.0 2.3 392 Camptonville 95.4 48.2 840 1.4~5 +3 0.081 38 10.0 2.2 560 La Porte 68.5 57.5 1518 2.40 0 0.261 66 5.0 1.9 1,123 Grizzly Ridge 59.9 94.9 2103 2.40 0 0.159 60 0.9 1.8 2,425 Lake Davis 65.7 106.8 1758 2.40 0 0.180 44 0.1 2.2 3,405 Sierraville 84.2 106.9 1516 2.40 0 0.014 27 0.5 1.8 3,649 5