WMOD00456

• Project Name: Sierra Ecology Project
• Title: The Sierra Ecology Project - Volume III
• Date: 1/1/1982
• Weather Modification - Doc Type: Report

Table 3.- Dates on which 25,50, and 75 percent oj the precipitation jell, 1899-1974-Continued
Year 25 percent fell 50 percent fell 75 percent fell
1943 Jan. 2 Feb. 8 Apr. 11
1944 Nov. 13 Feb. 1 Mar. 16
1945 Nov. 15 Dec. 22 Feb. 7
1946 N ov. 22 Jan. 29 Mar. 10
1947 Jan. 2 Mar. 9 Apr. 9
1948 Dec. 13 Feb. 7 Mar. 16
1949 Jan. 14 Jan. 28 Mar, 24
1950 Nov. 19 Dec. 8 Feb. 4
1951 Dec. 3 Jan. 12 Feb. 23
1952 Dec. 10 Jan. 14 Apr. 14
1953 Dec. 20 Feb. 13 Mar. 10
1954 Dec. 3 Jan. 16 Mar. 30
1955 Dec. 20 Dec. 26 Jan. 27
1956 Jan. 9 Feb. 24 Mar. 30
1957 Jan. 2 Feb. 15 Mar. 30
1958 Jan. 9 Feb. 10 Mar. 23
1959 Jan. 25 Feb. 9 Mar. 12
1960 Nov. 26 Feb. 12 Mar. 28
1961 Jan. 12 Feb. 10 Mar. 2
1962 Dec. 2 Feb. 1 Apr. 7
1963 Nov. 14 Jan. 19 Mar. 13
1964 Dec. 22 Dec. 26 Feb. 27
1965 Nov. 19 Dec. 25 Jan. 6
1966 Dec. 5 Jan. 30 Apr. 6
1967 Dec. 7 Jan. 30 Mar. 8
1968 Dec. 22 Jan. 20 Feb. 15
1969 Dec. 21 Jan. 16 Feb. 13
1970 Nov. 30 Dec. 28 Mar. 24
1971 Dec. 22 Jan. 26 Mar. 23
1972 Dec. 8 Jan. 16 Feb. 24
1973 Nov. 18 Jan. 15 Mar. 12
1974 Dec. 5 Jan. 9 Feb. 8

intensity (greater than 1.5 standard deviations above the mean) occurred in 9 years.. Low precipi-
tation intensity (1.5 standard deviations below the mean) occurred in only 3 years. Table 4 lists the
individual years by 0.25 cm (0.10 in) per day class.

Seasonal Precipitation

Fall.-Fall precipitation totals (October 1 through December 31) show increasing variability
toward the later years of record (fig. 6). The early years (1900-1912) exhibit a very even distri-
bution of magnitude. Subsequently, however, fall precipitation amounts begin to vary consider-
ably from year to year. Since 1912, only two periods (1928-30 and 1940-42) of 3 consecutive years

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