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protecting gages from the wind in the absence of forest. For example, gages near Denver were placed in established suburban neighborhoods where most backyards were. enclosed by 6-ft high solid wood fences. In neighborhoods with such fences, in addition to many houses and large conifer and deciduous trees, clearings can be found with quite limited winds at gage orifice level. Wind speeds were routinely observed at gage height at 3 such Denver suburban locations and were found to be light during the large majority of snowing hours, even when winds were strong at tree top levels. 5.3 Equipment The resolution of Belfort Universal gages determines the minimum hourly S accumulation that it is practical to work with. As discussed by Super and Holroyd (1996), the minimum resolution with careful chart reading using magnification is at about 0.005 inch h-l with standard 8-inch diameter orifice gages. All chart readings were double checked for accuracy. In addition, all outlier readings in comparisons between gage and SAA estimates of S, and all readings with heavier hourly accumulations, were checked yet again. The minimum gage resolution was considered to be 0.005 inch for all Universal gage data used in this study, including the Grand Mesa where twice standard area orifices were used, providing a smaller minimum resolution which was ignored in all analyses. A similar minimum radar hourly accumulation has been achieved by not accumulating S rates until the measured Ze equals or exceeds 5 dBZ. Using p = 2.0, the 5 dBZ value is equivalent to 0.010 inch h-l for a = 50, 0.006 inch h-l for a = 150 or 0.004 inch h-l for a = 300. Use of as dBZ threshold reduces far range virga contamination while providing radar estimates in line with the resolution of surface observations. Any recording gage may have timing uncertainties, for example, in setting the time on paper charts. Snow sometimes builds up on the sides of the orifice and later drops into the recording mechanism. Gages with small orifices can also be capped by heavy snow, leading to no snow being recorded during the actual snowfall and then an abrupt apparent large snowfall when the cap falls into the gage. These delayed drops of built up snow may occur under clear skies when the sun warms the gage sufficiently to break the adhesion of the snow to the orifice. Capping was not a serious problem with the frequently visited gages used in this study. The potential for capping was greatest on the Grand Mesa but it was avoided by using extra large orifices. Snow boards, which are manually read, generally provide the most accurate records of snowfall. They are set flush with the snow or ground surface. However, if placed in windy sites, they may be affected by drifting and scouring of the snow, resulting in greater or lesser records of snowfall than actually occurred. Windy sites must be avoided for any quantitative snowfall measurements. Snow boards have the disadvantage of having to be read manually and frequently; they are not good for unattended operations. Snow board accumulations have a practical resolution of 0.01 inch, the least value usually reported except for "trace" accumulations. The latter were ignored for all observations in the Albany area and for the single Denver snow board (site 7), resulting in a minimum resolution of 0.0 1 inch for all snow boards. Observations from near Albany were from snow boards in generally protected locations according to John Quinlan, Lead Forecaster at the Albany Forecast Office. Quinlan set up and oversaw a large volunteer network of snow boards. He had several conversations with the authors and was well aware of the need to avoid windy locations. Snow boards were used alongside gages in the Denver network to provide snow density information. 12