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Show This report discusses a continuation of experiments first described in Miscellaneous Report No. 3: MAN- MADE NOMINAL WIND ACTION AREA, published in June, 1962. This report compared precipitation observed with an unshielded precipitation guage and one shielded by the large circle of snow fence illustrated in Diagram No. 1. Purpose of this fence arrangement was to minimize wind effects and provide an accurate sampling of precipitation in an area of high storm winds, Berthoud Pass, Colorado. During the fall of 1962, the modifications were made to the snow fence area and during the winter comparisons were again made between the catches of the two recording gauges ( 775- B's) Modifications were as follows ( See diagram No. I) 1. Reduced air gap between ground and bottom of fence. 2. Reduced width of personnel entrance. 3. Increased distance of gauge orifices below top of double- layered fence. 4. Reduced amount of single fence at top of installation. 5. Due to settlement and stabilization of new fill did away with the mass of internal bracing. Comparison data between the two winters were compiled and they show that in the winter of 1961- 62 the Q- 12 Park-( unshielded) guage averaged 19% more than the " Corn Crib" guage, while this winter ( 1962- 63), the emphasis shifted to the " Corn Crib" recorder. This guage then averaged 12% more than the 0- 12 Park Recorder. As can be seen in Fig. 1. during the winter of 1961- 62 the 0.- 12 precipitation was always greater than the " Corn Crib" guage, while during the winter of 1962- 63 the '' Corn Crib" guage was consistently ahead of the Q- 12 precipitation, but |