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I I I I I I I I I I I I I I I I I I I 2. Events where precipitation was> 0.2 and ~ 0.8 inch occurred with hi ghest counts in the temperature category -11 to -20 oC in both the Mogollon Rim and the southern mountains. 3. Events of > 0.8 inch occurred most frequently with temperature categories -11 to -20 oC and < -27 oC, with the initial interval somewhat predominant. 4. Essentially, precipitation events did not occur with 500 mb tem- peratures in the interval -5 to -10 oC. Tables 13-17 indicate the results of cross-tabulation of precipitation by winter type and 700 mb wind speed for the station groups under study. The wind speed at this level, approximately 3000 meters (10,000 ft), is frequently indicative of the transport of moisture up the barrier. The intervals selected for study were: < 3.5 mis, 3.5 to 10 mIs, 11 to 15 mIs, 16 to 20 mIs, ~ 21 m/s. Two results were noted. 1. For the precipitation interval ~ 0.05 and ~ 0.2 inch, counts for the Mogollon Rim and the southern mountains were highest with winds of 3.5 to 10 m/s. Wind speeds in this interval are frequently preferred for cloud seeding. 2. Very few precipitation events occurred during the dry winter, accompanied by wind speeds exceeding 10 m/s. This tendency was less apparent in normal and wet winters. Results are given in tables 18-22 of cross-tabulation of precipitation amount by winter type and the 700 mb wind direction obtained from the Winslow rawinsonde analysis. Before summarized results are given, some discussion regarding the winds below 700 mb is in order. The wind direction at this level is generally indicative of the source of air mass flow approaching the barrier. The direction is important. because it is a vital element contributing to the cross-barrier component available to transport the air layers over the barrier and allow moisture condensation. Certain wind directions favor precipitation in 43