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I I I I I I I I I I I I I I I I I I I Considerable programming and testing were needed to produce a version of the SAA that could use Level III data. The Level III product is in the form of binary files intended for visual display, not for use as discrete digital dBZ values. Each Level III reflectivity interval had to be assigned a dBZ value. Use of midpoints was shown to be too simplistic for greater reflectivities. However, the SAA can now run successfully with archived Level III reflectivity files. Parallel runs of the SAA, using Level II and Level III reflectivities as input, were made for five major Minnesota snow storms, one with mixed rain and snow. The degree of agreement was shown to be quite good, especially at ranges less than 150 km where radar estimates are most reliable. Most Level III runs had area average SWE accumulations within 10 percent or less of the standard Level II runs for the same volume scans, at least within 150 km range. These results indicate that use of archived Level III data from Minnesota snow storms provides quite reasonable SWE estimates using Level II estimates as the standard. The next step in this applied research will be to continue work on the VPS range correction scheme so that the SAA can apply appropriate corrections for all ranges between about 50 and 150 kIn and perhaps farther. It would, of course, be very desirable to test this scheme against "ground truth" SWE observations. Accurate surface measurements of snowfall, either of depth or SWE, are difficult to find. However, attempts will be made to find the means to test the SAA range correction scheme against some surface observations. 5. REFERENCES Andrieu, H. and J.D. Creutin, 1995: Identification of Vertical Profiles of Radar 'Reflectivity for Hydrological Applications Using an Inverse Method: Part I: Formulation. Journal of Applied Meteorology, 34, 225-239. Crum, T.D., R. 1. Alberty and D. W. Burgess, 1993: Recording, Archiving and Using WSR-88D Data. Bulletin of the American Meteorological Society, 74,645- 653. Joss, J. and R. Lee, 1995: The Application of Radar-Gauge Comparisons to Operational Precipitation Profile Corrections. Journal of Applied Meteorology, 34, 2612-2630. Joss, J. and A. Waldvogel, 1989: Precipitation Estimates and Vertical Reflectivity Profile Corrections. Preprints, 24th Conference on Radar Meteorology, American Meteorological Society, Tallahassee, FL, March 27-31, 682-688. Joss, J. and A. Waldvogel, 1990: Precipitation Measurements and Hydrology. Radar in Meteorology, D. Atlas, Ed., American Meteorological Society, 577-606. 23