The variations in United States cloudiness (percent of sky covered by clouds, as estimated subjectively by observers at 100 National Weather Service stations) and sunshine duration (percent of possible sunshine, as estimated objectively by sunshine recorders at these same 100 stations) are examined for years 1950–88. During this period, the correlation between annual values of cloudiness and sunshine duration within the contiguous United States was −0.86, significant at the 1% level. The years of maximum cloudiness and minimum sunshine duration were 1972 and 1982, when strong El Ninos began. The year of maximum sunshine duration was 1988, but the years of minimum cloudiness were 1952–56 (mini dust bowl); the discrepancy a result of the greater long-term increase in cloudiness than decrease in sunshine duration. In the spring of 1988 them were anomalous values of cloudiness (below average) and sunshine duration (above average) in north central, south central and southeast regions of the United Sta... Abstract The variations in United States cloudiness (percent of sky covered by clouds, as estimated subjectively by observers at 100 National Weather Service stations) and sunshine duration (percent of possible sunshine, as estimated objectively by sunshine recorders at these same 100 stations) are examined for years 1950–88. During this period, the correlation between annual values of cloudiness and sunshine duration within the contiguous United States was −0.86, significant at the 1% level. The years of maximum cloudiness and minimum sunshine duration were 1972 and 1982, when strong El Ninos began. The year of maximum sunshine duration was 1988, but the years of minimum cloudiness were 1952–56 (mini dust bowl); the discrepancy a result of the greater long-term increase in cloudiness than decrease in sunshine duration. In the spring of 1988 them were anomalous values of cloudiness (below average) and sunshine duration (above average) in north central, south central and southeast regions of the United Sta...