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<br />correction scheme is being dealt with for precipitation in general by the NWS Hydrologic Research <br />Laboratory (O'Bannon, 1998). Other desirable improvements for the SAA are discussed in this report. <br /> <br />1.4 Annual Progress <br /> <br />This final report discusses Reclamation's activities and findings during the past 3-year effort of SAA <br />development. Work done during the first year was reported by Super and Holroyd (1996). High quality <br />data sets were gathered during the 1995-96 winter from gages and snow boards deployed within range of <br />the Denver, Colorado, Cleveland, Ohio, and Albany, New York, WSR-88Ds. A prototype SAA was <br />discussed in the 1996 annual report which was capable of operating after-the-fact using archived Level II <br />data. As discussed by Crum et aI. (1993), Level II data are the most basic available to researchers using <br />copies on 8-mm tape. Level II data are the same as those transmitted from the RDA (Radar Data <br />Acquisition) or radar computer to the RPG (Radar Product Generator) workstation where all algorithm <br />processing is done. A key measurement provided on Level II data tapes is Ze, to 0.5 dB resolution, for <br />each l-km by 10 range bin out to a 230-km range. A range bin is the basic spatial unit for which these <br />data are recorded. Doppler velocities and spectrum width are also provided, but at 0.25-km by 10 <br />resolution. <br /> <br />Work done during the second year of SA A development was reported by Super and Holroyd (l997a). <br />The SAA was adapted by NSSL (National Severe Storms Laboratory) personnel with Reclamation help <br />to operate in real time. Real-time field tests were performed at Minneapolis and Cleveland during the <br />1996-97 winter. During that same winter, Rec lamation gages were operated within range of the <br />Minneapolis, Minnesota, and Grand Mesa, Colorado, radars. <br /> <br />Data were also gathered during the 1996-97 winter from radars near Anchorage, Alaska, Beale AFB, <br />California, and Seattle, Washington. Unfortunately, only limited Level II data were obtained for a <br />variety of reasons including maintenance problems, limited dry snowfall periods over the Sierra Nevada <br />and Cascades, and a dry winter in Alaska. Snowfall data from the areas covered by these 3 radars were <br />obtained from other agencies with mixed results since their gages were sited for purposes other than <br />comparison with radar. Final analyses of existing Alaska, California, and Washington data sets, <br />hopefully to be complemented with additional observations, will be reported in a supplemental report to <br />the OSF due September 1999. <br /> <br />Work done during the third year of SA A development consisted mostly of analyzing the acquired data <br />and refining the SAA as reported herein. In addition, the SAA was tested in real time at Albany, <br />New York, with good results. <br /> <br />2. TASK SUMMARIES <br /> <br />Briefly, tasks stated in the MOU (apart from reporting requirements) and resulting accomplishments are: <br /> <br />1. Scrutinize existing precipitation gage observations of S from the J 994-95 winter within <br />reasonable range ofWSR-88D systems with Level II data: Existing hourly precipitation gages are <br />few and are generally inadequately sheltered from wind. <br /> <br />2. Obtain Level I1 data from selected WSR-88D systems and storm periods for the 1994-95 winter <br />that have corresponding gage data. Also obtain supporting software from the OSF for <br />manipulation of these data and hardware suitable for working with these data and software: <br /> <br />3 <br />