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One to a few storms at each site produced most of the seasonal total supercooled liquid water flux. From 50 to 67 pet of all storms at each site produced small amounts of supercooled liquid. ~ SUMMARY AND CONCLUSIONS Storm total SL W flux estimates and precipitation measurements were examined with data sets from 4 mountain regions; the Mogollon Rim of Arizona; the Orand Mesa of Colorado; and the Tushar Mountains and the Wasatch Plateau of Utah. Periods with microwave radiometer observations ofSLW were limited to 2 mo on the Mogollon Rim and Wasatch Plateau, and to 5 mo at the two other sites. An apparently significant relationship (rank correlation coefficient) existed between larger flux-producing storms also having greater preCipitation amounts. When the effect o~ storm duration was removed, the partial correlation coefficient between flux and precipitation was still significant at 3 of the 4 mountain regions. Significant partial. correlations existed between precipitation and storm duration. (controlling for flux) at all locations. None of the four data sets support the concept that large precipitation-producing storms are highly efficient in converting SL W flux to snowfall. The reverse was indicated; that is, storms with larger precipitation totals tended to have greater SL W flux. This indication suggests that large SL W flux- producing storms may be efficient in snowfall production during some phases and inefficient during other phases. One example from a moderate-sized Utah storms supported this conceptual picture. A comparison of precipitation flux to SL Wand ice flux was used as a means of computing precipitation efficiency. The prefrontal stage of this storm was very inefficient and contributed most to the total SL W flux. The frontal stage had a higher SL W productions rate, but was more efficient and of shorter duration, and thus contributed less to the total SL W flux. The post frontal stage contributed the least to the total SL W flux. It was also found that the final postfrontal stage was only about 60 pet efficient even though almost no SL Wexisted. Much of the radar-estimated cloud ice apparently did not fall to the ground as precipitation; The frequency of small SL W-producing storms (<50 Mg flux per meter) was similar at all four locations, ranging from 50 to 67 pet of all storms. The frequency of large storms, with greater than 400 Mg m-I ranged from 0 to 9 pet. Both the Wasatch Plateau and the Orand Mesa had a single exceptionally large SL W -producing storm exceeding 100 Mg m-l. In each area one to a few storms produced most of each seasons's SLW flux. The storm frequency was markedly higher for the Orand Mesa, averaging 13 storms per month compared with 8 storms per month over the Wasatch Plateau, 5.5 per month over the Mogollon Rim and 5.4 per month over the Tushar Mountains. However, total observational periods for these mountain areas were limited. While a higher frequency of storm passages would be expected at more northern latitudes (i.e., the Wasatch Plaieau and the Orand Mesa), a longer sampling period would be needed to determine if sign.ificant differences really exist in SLW episode frequency. Distributions of storm durations are similar in Tables 1,2 and 3, with from 50 to 70 pct of all storms lasting less than 24 hours. Only 3 of 11 (27 percent) of the Mogollon Rim storms listed in Table 4 were that brief. , . , Because seeding potential can be expected to be related to SLW flux (among other factors), the major SL W -producing storms obviously should be identified for treatment. Identification can be done with real- 48