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<br />Level II data were recorded only at sites too far south for exclusion of bright band contamination <br />and were therefore not suitable for study. <br /> <br />3. Use the data, software, and hardware of tasks No. 1 and 2 above and write additional software <br />as needed for development of a "simplified prototype" Algorithm for prediction of S from WSR- <br />88D Level II data. The initial Algorithm will be based on comparisons of radar measurements of <br />equivalent (also called effective) reflectivity factor, Ze' with surface gage measurements ofS. <br />The Algorithm will incorporate radar-estimated horizontal wind speed and direction for <br />advection of falling snow particles to match surface observations of S with radar bin <br />observations of Ze' A large number of Ze-S pairs will be used to calculate the empirically- <br />determined coefficients, a and p, for the commonly-used power-law model:, Ze = aSP: The <br />development of the prototype SAA used new, 1995-96, data from specially deployed gages and <br />nearby radars at Denver, Cleveland, and Albany. The advection scheme was successfully <br />designed. However, it was found to offer no improvement (compared to using the nearest <br />neighbor uncluttered range bin directly above the ground location) in the calculations of Sand <br />was too costly in computer time to retain in the SAA. <br /> <br />4. Collect high-quality observations ofS and SD during the winter/spring of 1995-96 near Denver, <br />Colorado. This was done at several sites. <br /> <br />5. Obtain good-quality observations ofS and SD in a climatological area with WSR-88D coverage <br />other than the Denver area during the winter /spring of 1995-96: The Albany FO ofthe NWS <br />installed and operated a large volunteer observer network using snow boards. They furnished <br />numerous hourly Sand SD measurements to Reclamation. <br /> <br />6. Based on the MOU Supplement No.1 of August 1995, install and maintain five Belfort Universal <br />recording precipitation gages from mid-November 1995 through March 1996 between the near <br />andfar ranges of the Cleveland WSR-88D: The gages were deployed parallel to the south shore <br />of Lake Erie. The main purpose of this line of gages was to investigate lake effect storms and the <br />ability of the WSR-88D system to detect snow and estimate snowfall accumulation as a function <br />of range. <br /> <br />7. Reduce the precipitation gage charts for several lake effect storms of particular interest (task 3. <br />of MOU Modification No.1): This was done for all 24 storms, mostly lake effect, identified <br />during that unusually wet winter. <br /> <br />8. Refine the SAA with the 1995-96 winter observations from the two areas specified in 4.a.(4) and <br />4.a.(5) of the MOO, and expand it to include predictions ofSD as specified in task 4.b.(l) of the <br />MOU' This was done for Denver and Albany. SD was estimated based upon typical snow <br />density. <br /> <br />9. Optimize the SAAfor lake effect storms using the Cleveland area S observations collected during <br />the 1995-96 winter (task 2. of MOU Modification No.1). Special emphasis is to be placed on the <br />ability of the NEXRAD to detect and quantify snowfall as afunction of range: The Cleveland <br />data were almost all from lake effect storms. The range effect was measured with a line of <br />5 gages. <br /> <br />10. Use real-time surface observations ofS to adjust radar estimates: By memo dated October 2, <br />1996, which accompanied MOD Modification No.2, Task 4.b.2 was deleted. It now appears <br /> <br />4 <br />