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294 JOURNAL OF APPLIED METEOROLOGY VOLUME 29 the 4 to 5 km region, increasing reflectivity below the -50C level due to aggregation on the lower half of the barrier, and an apparent bright band below the OOC level in this same region. . Table 1 provides microphysical information at the location of the letters annotated on Fig. 3. These letters will be used in the following discussion. Cloud base over the valley was approximately 1.8 km (all heights MSL), near the melting level, and droplet concentra- tions were 100 to 200 cm -3 within 300 m of cloud base (A). Aggregates of dendrites, some greater than 4 mm, were observed from cloud base to 4 km (A-C) where the ICC reached a maximum of 30 L -1. Above 4 km ice particles became less aggregated and habits changed to platelike crystals with concentrations < 1 L -1 (D). Cloud top was near 4.7 km, -170C, in this vicinity (E). Cloud tops varied between the valley and crest locations. As the cloud physics aircraft descended to- wards KGV (E-G) it did not encounter cloud until reaching 4 km, -130C (G). The few ice particles ( <5 L -() observed there were 500 to 800 ~m plates. On descent along MOCA (H-O) appreciable liquid water, up to 0.4 g m -3, was found from near the crest at an altitude of 3.8 km, -1OoC (H), to approximately 2.5 km, -20C (M). Ice crystal types included a few large dendrites, small 200 to 300 ~m plates or columns, and graupel of 1 to 2 mm. Needles were noted near the -50C level (K, L). All ICC were <10 L -1 until near the melting level where aggregates of irregulars (M), 2 to 3 mm, and aggregates of dendrites (N), 5 to 6 mm, approached 20 L -I. On ascent back to the -80C level (O-R) to begin the seeding classification run the ICC was 10 to 30 L -1. Large aggregates up to 8 mm (Q) and patches ofliquid water up to 0.4 g m-3 (P) were also noted. These observations indicate that the ice crystals were predominately dendrites, and that aggre- gates of dendrites produced the radar echoes and the main precipitation-size particles. The cloud physics aircraft performed the classifica- tion run along the seedline 1730-1740, from location S to R in Fig. 3; and liquid water content was >0.05 g m -3 for only 3 s. This was not sufficient for the cloud to be classified as seedable; however, mountaintop icing stations at Signal Peak and Squaw Peak both indicated steady SLW contents of 0.2 g m -3, and a mean of 0.4 mm ofliquid was observed on the radiometer at KGV from 1720-1740, Fig. 4. The Ka-ban~ radar at KGV showed cloud depth to be 1 km, indicating an average SL W content of 0.4 g m -3. This agrees generally with the SL W measured by the cloud physics aircraft at the mountain crest and along the MOCA descent. This liquid was thus located near the crest and generally