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these 11 occurred during the 1984/85 winter field season which was evidence of the persistence of flow fields and storm types experienced in one given winter. Nine storms had complete radio~eter data .sets. The variations in this category revolved around the actual trajectory of the storm. In onshore systems, similar to the case discussed, the center of the system moved directly over the project area. Typical values of supel'cooled water ahead of the front were 0.05 to 0.50 mm with peak measurements to 1.00 mm. Typical pre-frontal supercooled water episodes ranged from 6 to 8 hours. Pre- cipitation rarely occurred in the pre-frontal region. Supercooled water generally decreased to 0.05 to 0.20 mm within the frontal band and after frontal passage. Precipitation was greatest with the frontal passage. Precipitation decreased after the frontal passage. Precipitation and supercooled water ended with the trough passage. Storms with inland trajectories provided continuous liquid water with little or no precipitation. Supercooled 'rJater values were typically O.IO to 0.40 mm through the. entire storm. The storm duration was 15 to 21 hours. No distinct frontal structure was observed in these storms. Offshore storms were usually very cold, sometimes producing significant amounts of snow near sea level. Winds over the Sierra Nevada were weak at all . . levels. Sustained amounts of supercooled water were rarely observed in the cold trough which was dominated by strong convection. Convective peaks of super- cooled water sometimes reached 0.50 mm, but again were very short lived. Precipita,tion was typi.cally 3 mmh-1 and as high as 6 mmh-1 witllin convective regions. The duration of offshore storms was as long as 57 h, indicative of the formation of the slow moving cold deep trough. 24 .I