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Flueck, J. A., and W. L. Woodley, 1985: A guided linear model "sweep out" method for both exploration and confirmation of treatment effects with application to the FACE project. Proceedings, 4th WMO Scientific Conference on Weather Modification. A Joint WMO/lAMAP Symposium, Honolulu, HI, August 12-14, 1985. World Meteorological Organization, Geneva, WMO{TD-No. 53, 311-316. No abstract. Frisch, A. S., E:. W. Orr, and B. E. Martner, 1992: Doppler radar observations of the development of a boundary-layer nocturnal jet. Monthly Weather Review, 120:3-16. A single Doppler radar obtained detailed clear-air measurements of the development of a strong boundary-layer nocturnal jet in North Dakota during the summer of 1989. The evolution of the jet was monitored by the radar with a high degree of vertical and temporal resolution using a repetitive sequence of four different elevation scans. A new variation of the velocity-azimuth display (V AD) analysis technique provided vertical profiles of the mean wind components and several turbulence terms. Boundary-layer wind speeds began to increase in the late afternoon, well before sunset, as surface cooling began. Wind speeds accelerated faster after sunset and eventually produced a jet that exceeded 23 m S.l at about 0.5 kIn AGL. The wind veered with height and time and followed the expected inertial oscillation pattern. Measured shear stresses, vertical fluxes of momentum. and velocity variances, which were initially large, decreased sharply after the surface began to cool. The directly measured vertical velocities were significantly downward during the late afternoon and upward at night. Fuhs, M. J., 1986: North Dakota hail suppression analysis using crop-hail insurance data. M.S. thesis, Department of Meteorology, South Dakota School of Mines & Technology. Rapid City, SD, 53 pp. + appendices. Except in 1955-1957 and 1960, operational cloud seeding programs have been conducted in North Dakota every year since 1951. Seeding from aircraft started in 1961 and weather radar was added in the mid-1960s to increase the lead time in treating hailstorms. North Dakota has the longest-running hail mitigation program in the world using aircraft. The an,a1ysis used for this project involves crop hail insurance data from the Crop Hail Insurance Actuarial Association (CHIAA). Historical trend analysis using weighted loss/cost (WLC) values is examined for non-seeded and seeded years both in target and control areas. The overall trend suggests long-term hail reductions of 23% and 7% in seeded areas using mean and median values, respectively, from the Double Ratio. The Mann-Whitley U rank test gives a level of significance of 0.02 that WLC values are lower during the seeded years compared to the non-seeded years when all target counties are compared with eastern Montana control counties. Sub-target areas generally have levels of significance above 0.10 when compared with adjacent control areas. Scatter plot analysis generally shows lower hail losses for the seeded years. A cumulative double mass analysis gives a hail loss reduction of about 22% for North Dakota target counties when compared with eastern Montana. The North Dakota Cloud Modification Project appears to be paying for itself in apparent hail reduction success alone. A benefit to cost ratio of 3.7: 1 exists when all crop savings are evaluated for North Dakota target counties. If the project is also successful in its rain enhancement objectives, greater benefit to cost ratios may result. ' Fukuta, N., and C. Redder, 1988: Development of superior equations of ice crystal growth microphysics for modeling and analysis. Final Report to Utah Department of Natural Resources, Division of Water Resources. University of Utah, Salt Lake City, UT, 112 pp. No abstract. 36