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. . . presumed to provide the best estimate. This scheme could be modified to weight the accumulation values by range, thereby giving some emphasis to measurements from each radar. This latter approach would provide a smoother pattern than the existing scheme which sometimes has discontinuities along the straight line representing equal distances from two adjoining radars. However, the intent of the current scheme is to emplhasize such differences. Since the Ze-S relation, range correction scheme and all adaptable parameter settings are identical for all 5 of the radars, differences between adjoining radars are most likely related to calibration errors, or possibly to an antenna being out of level. It has been found that the SAA products from the Aberdeen, Grand Forks and Minneapolis radars are usually in good agreement along their respectivE~ equal range lines. That is, little or no discontinuity is seen in resulting merged snow accumulation patterns. Conversely, the Bismarck radar and especially the Duluth radar consistently provide lowest accumulations than their neighbors. Therefore, it is suspected that these two radars may be "running cold," providing erroneously low reflectivity values because of calibration problems. An alternative explanation is that the other 3 radars are all "running hot." The latte~r possibility seems less likely since all 3 radars would have to have very similar calibration errors because they agree with one another. As noted, having an antenna out of level could result in the observed errors. This is considered unlikely because it should be easy to maintain proper antenna leveling. These findings of differences among radar snow estimates have been pointed out to personnel at the NEXRAD Operational Support Facility and the Duluth NWS Forecast Office. Maintaining proper radar calibrations across the national network: is clearly the responsibility of the three agencies operating the network. One may view many SAA graphical products for the 5 individual radars for the past 1, 2, 3 and 6 h. The merged HRAP field for all 5 radars is provided for the past 3 and 6 h. All of these products are updated each hour. Fixed 6 hand 24 h periods are also displayed for the past week. The Reclamation web site with SAA products is: www.usbr.gov/rsmg/ click on NEXRAD Snow Algorithm Products. Posting of these many products was done at the request of NWS personnel at Chanhassen, MN. Once it was realized that Reclamation was already calculating hourly products and summing them for the daily periods desired by NOHRSC, providing short-term areal distributions of SWE and SO for NWS forecasters and others seemed to be an obtainable goal. While production and display of these SAA products was beyond the scope of the Goals stated above, there was a clear need for such products by NWS Forecast Offices. This was especially obvious to the Chanhassen NWS personnel because they had used the SAA in real time during 1996-97 winter field tests with Level II reflectivites. They were well aware of the value of the SAA snow estimates (Naistat et al. 1998), and desired to have them available once again. The Chanhassen Forecast Office has provide considerable valuable feedback which is helping us improve the SAA products as the winter progresses. For example, the minimum dBZ value converted to non-zero precipitation has been shifted 3 times in an attempt to balance good performance during snow storms with minimizing false snowfall indications during virga episodes caused by reflectivites from mid-level clouds. Test runs were also made with and without range correction since range correction exacerbates the virlga contamination problem. The current approach uses range correction and the lowest minimum reflectivity possible with N I OS data which 4