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Show which is not surprising considering the complications of actual terrain, non. steady- state data for input, and convective and storm components. The values, in general, appear to be too low at the start of the windward slope and fall off too rapidly on the lee slope. This prediction should be improved if the ridge profiles are calibrated and a more accurate analysis is made of the storm and convective components. It should be pointed out that the crest of the smoothed mountain profile in this case has been placed near False Top, which places Rabbit Ears Pass significantly over on the lee side. In actuality, the Park Range is quite flat on top with a broad area (8-l0km wide) of nearly the same elevation. Thus, assnming the crest to be at the west edge of this high, relatively flat area may result in underestimation of precipitation for high elevation areas downwind such as Rabbit Ears. Several other examples of output of the model will be presented to indicate the behavior of the model under various input data profile conditions. Two cases on 29 January 1969 are presented in Figures 27 and 28. The case at 1900 MST was characterized by extremely strong flow at very low levels. The downdraft area over and in the lee of the mountain is particularly strong, The last contour drawn by the computer is -1. 0 msec - l and the maximum negative vertical velocity was -1. 38 msec- 1 . Note also the strong lee wave positive vertical velocities computed. Figure 29 gives the predicted orographic component of precipitation. The second or 1900 case gives the high readings and peaks at 0. 86 cm in three hours just before the ridge top. This analysis period (number 2 7) was the subject of an extensive case study in Progress Report No. 43. For the first 3-hour period the precipitation measured at False Top was 0. 135 cm and for the second, 0. 32 cm. There was, however, probably a fairly large storm precipitation component involve in this case. The second period 1700-2000 MST was the seeded period. The presence of silver was unequivocally proved during the second period in both replicas and snow samples taken at Rabbit-Ears (Progress Report No. 43). The last case is for 16 February at 1902 MST and illustrates the vertical velocity field for a sounding with strong flow near the surface, layers of ver1 light flow aloft, and stable layers in the sounding. Figure 30 is the vertical velocity field computed for this case. The computed precipitation distribution is plotted in Figure 31. The precipitation amounts are very high over nearly all of the windward slope and, unlike the previous ·cases, high amounh extend on over the lee side of the crest. The observed three hour totals wert 0. 071 cm at Emerald Mountain, 0. 05 cm at Valley View, 0. 55 cm at False Top, 0. 147 cm at Rabbit Ears, 0. 08 cm at Mt. Harris. A summary of comparisons of model output to observations is given iri Section 5. 1. 54 \) w 1/) \ ), I\) 0 J w > |