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for at least one of six recording precipitation gage sites. Due to the 40 elevation angle used in radar recording, this type was believed to be a shallow orographic cloud system. The NOAA WPL radiometer indicated some supercooled liquid water when this type was present approximately 72% of the time. Frontal and upper level cirrus passage times were determined for each storm. The upper level cirrus usually occurred before the surface frontal passage. The no echo precipitation echo type described above frequently occurred following the cirrus passage but before the frontal passage, lending support to a shallow orographic cloud interpretation. I ~ ~ Recording precipitation gage data indicated a significant orographic component to the precipitation pattern during the observed storms. I I 1 ~ An analysis of the surface icing rate detector at Mt. Holly versus radiometer derived liquid water contents indicated that liquid water was normally observed by both instruments. This tentatively indicates liquid water at lower levels in the clouds is a frequent occurrence. B. 1985 Operations The multi-agency field project was carried out from January 15 through March 15, 1985. NAWC's responsibilities addressed the general question of seeding material transport. These studies utilized two basic approaches: SF6 tracer gas releases, and constant altitude balloon tracking studies. SF6 and constant altitude balloons were released from valley locations. Air samplers were placed at various valley locations plus ridgetop locations. The ridgetop locations were services by heli- copter. Despite some problems with the samplers due to the cold weather, significant data were acquired. In one case SF6 released from a valley location was transported through a low-level inversion to eight of the ten ridgetop sampling locations. The other two samplers were not oper- ative. Several tracks of constant altitude balloons were acquired. Pressure, temperature, and relative humidity were also acquired on these tracks. Plans for the 1985-86 winter include the testing of a different type of air sampler for cold weather applications. This feasibility study would be conducted for a one month period in February through March time frame. More in-depth analysis of the data collected during the 1984-85 winter is also underway. 4. Technology and Meteorol~gy from the Dual-Wavelength Radiometer and the K-band Doppler Radar A. NOAA/WPL Microwave Radiometer Amounts of liquid observed at -Beaver, Utah, in 1985 were somewhat lower than observed during the 1983 season. The median liquid, nor- malized to the zenith, was 0.05 mm in '1985 compared to 0.13 mm in 1983. The difference may be due to part to the change in radiometer location 40