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, . ,. . . . . . . . . . . . . . . . . It .. . . .. . ,. = . . = .. . .. . .. . .. II>> It .. north and west about 23% of the time, between north and east in 8% of the soundings, and between south and east in only 5% of the soundings. March and April had the greatest variety in wind directions, but even then, when upslope storms are common on the Front Range, the Gunnison project area rarely received amounts over 0.5" from easterly-type events. November- February events were almost exclusively from a westerly direction. Many of the soundings were dry below 650 or 700 mb. Some showed only a 100- or 200-mb thick moist layer, usually found between 500 and 700 mb. The clouds that were formed in these situations over the proposed target area were no doubt thicker than these numbers would indicate due to the forced lifting of the lower levels due to the mountain barriers. Of the soundings examined, the 700-mb temperature was -5 oC or below slightly less than half of the time, with the average being -4.1 oC. However, the 700-mb temperature was -2 oC or colder approximately 80% of the time. Figure 9 provides a plot of the mean storm 700mb temperature averaged by month. As expected, these average temperatures drop during the heart ofthe winter season. Although a -5 oC temperature is commonly used as a maximum threshold for wintertime seeding projects, much of the Gunnison project area is above the 700-mb level (with some peaks rising to near 600 mb) and thus the seeding material can be expected to rise significantly higher than 700 mb iftargeted correctly. This means that seeding is likely to be effective even when the 700-mb temperature is as warm as -2 oC, in which case the vast majority of these events are cold enough to be seeded from the temperature standpoint. 7