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SUMMARY -. A series offive aircraft missions tracked AgI and SF6 (simulated AgI releases) from valley and canyon mouth sites used in the Utah operational seeding program. All flights took place in VFR conditions to permit very low-level sampling over both mountainous terrain and within valleys. Each mission was flown under atmospheric conditions typical of prefrontal conditions during winter storms. In fact, snowfall was occurring at higher elevations during some sampling fljghts. Four of the five aircraft missions found that real and simulated seeding material was transported along the mountain barrier rather than over it, or the material was trapped by low-level stability and was drifting about the valley. The AgI and SF 6 were tracked over the Wasatch Plateau during part of one mission when the lower atmosphere likely had neutral stability. Ice nucleus concentrations were estimated based on the largest mean SF6 amount above the Plateau and the characteristics of the AgI generators used in Utah. It was found that ice nucleus concentrations would be very limited at typical SL W temperatures in the prefrontal storm phase. Acoustical counter measurements of IN supported this conclusion. Thus, even in the single case where plumes were transported in the layer over the Plateau where SL W is known to concentrate, resulting IN concentrations appeared inadequate for effective seeding. The present seeding approach may be effective during other storm conditions than those sampled. For example, the AgI may pool in the valleys for extended period and then be transported into the SL W region in higher concentrations during frontal passage, a possibility that has not been adequately tested. Unpublished observations from early March 1991 showed that storms with embedded convection transported valley-released AgI to aircraft sampling levels well above the Plateau. It will be interesting to analyze the resulting ice nucleus concentrations. .- The observations presented in this paper, together with those described in the Part I companion paper, strongly suggest frequent ineffectiveness in current cloud seeding methods in Utah. Steps should be taken to improve the frequency of targeting of the SL W region with AgI and to increase the concentration of seeded crystals when the SL W region is targeted. The technology exists to do both. Repeating the strong recommendation made in Part I: winter orographic cloud seeding projects should follow Utah's example and physically examine their targeting ifthey have not done so already. This question is too important to ignore. 1993 articles and papers: 8.6. Sassen, K., and H. Zhao, 1993: Supercooled liquid water clouds in Utah winter mountain storms: cloud-seeding implications of a remote-sensing dataset. J. Applie1 Meteorology, 32, 1548-1558. ABSTRACT. A polarization lidar, dual-wavelength microwave radiometer, and radiosonde dataset from 19 winter storms studied over the Tushar Mountains in the 1985 and 1987 Utah-NOAA cooperative weather modification field campaigns are used to characterize embedded supercooled liquid water (SL W) clouds. The findings show the dominance of barrier-level, mildly supercooled (0 0 to -10 oc) orographic clouds, as identified by the lidar from a midbarrier field site. The combined lidar and radiometer (with liquid 44