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<br />Jl~BSTRACT <br /> <br />This report documents an extension of work done on the Snow Accumulation Algorithm (SAA) <br />development for NEXRAD WSR-88D radars. An expansion of operational testing using Level ill data <br />shows that the algorithm continues to be robust. For the 1998-1999 season (November - April) a variety <br />of accumulation products were made available on the Internet for five radars across the Dakotas and <br />Minnesota, including a regional mosaic. The Ze-S relationship used was 150 R2.o. That network was <br />expanded to 10 radars for the 1999-2000 wint~~r season. <br /> <br />Issues involving the vertical gradient of reflectivity and snowfall continued to be prominent. The vertical <br />gradient of falling snow was used to generate a range correction which boosts integrations by a factor of <br />three at 230 km. The use of this correction scheme appears to be appropriate when compared to surface <br />observations. Experimental work was performed that reduces the effects of virga at far ranges. A <br />visualization routine was created to display the vertical gradient in the lowest 5 km of altitude above the <br />radar. Parts of that routine may be useful in future efforts to reduce virga and bright band effects. <br /> <br />Future work should continue to examine the vertical gradient issue to identify the best style of algorithm. <br />One that can simultaneously adjust for virga, bright band, and range correction would be preferred. In <br />addition, individual radar hybrid scan and occultation files can be adjusted by hand editing to reduce <br />blemishes in the SAA product. <br /> <br />Vll <br />