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Figure 4 The relationship (see ) is not a ‘perfect’ relationship by any statistical means however; there are some items to note. One is the notable tendency for ‘very wet’ years (> 120% of normal) to occur in years that the NAO was greater than 0.00 and the lack of ‘very dry’ (< 80% of normal), when the NAO value was greater than 0.00. As a secondary indicator, the AMO has a bit of scatter, when it comes to years when the leading mode value is negative. However, in years when the AMO is in a positive leading mode, there is a notable lack of excessively wet years (say, above 105-110% of normal) hinting that users may not count on excessive precipitation when such a pattern exists when planning supply scenarios. Some ‘secondary’ but, weaker relationships exist with the Pacific Decadal Oscillation (PDO) and minimal constructive relationships show up with the ENSO indicators. As the reader examines Figure 4 (and subsequent graphs similar in nature to it in this report) areas are shaded on the x and y-axes. Along the x-axis a blue line is placed at either the 100% of normal line in the case of precipitation or the mean value for variables such as volume runoff or days of precipitation above 0.10”. Normal as defined in the % of normal precipitation is for the all-year average of that variable for the period of record available. The horizontal green shading around the bar indicates near normal values (which are about +/- 15 to 20 % of normal based on the variable). The yellow shading along the y-axis is to delineate HCI values that are categorized as ‘neutral’ relative to the scale with which they are measured. Finally, each of the blue dots on each of the graphs represents a data point that plots the value of the measured variables (% of normal precipitation, seasonal runoff volume, ect.) vs. the measured HCI multi-month variable for a particular water year. 10