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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />291J <br /> <br />II-12 <br /> <br />another center just south of Pike's Peak in the Arkansas River drainage. <br />The maximum average depths of rainfall in this storm, i.e., computed without <br />reference to basin boundaries, were: <br />Duration (hours) 6 12 18 24 48 <br />Rainfall (inches) 1.3 2.2 2.8 3.5 4.7 <br /> <br />The above data are likely to be less accurate than those of more <br /> <br /> <br />recent storms since the raingage network in 1894 was far from adequate. The <br /> <br /> <br />average depths computed may be too low or too high, but they may tend to be <br /> <br /> <br />high with respect to the project basin because some of the heavy rainfall <br /> <br /> <br />included in these averages occurred in the Arkansas River Basin. <br /> <br />The representative 12-hour persisting dewpoint for the storm, as <br />o <br />determined by Hydromet at the time the storm was analyzed, was 62 F. The <br />maximum 12-hour persisting dewpoint for June 1 was determined to be 75oF. <br />If an inflow barrier height of 6600 feet (the average of the barrier heights <br />used ,by the USBR in transposing and maximizing the June 1964 storm) is used <br />in maximizing the May 1894 storm in place, the adjustment factor is 2.25. <br />The maximized values are given on line E of Table II-2. <br /> <br />The May 29 to 31, 1894 storm, which was of the same type as the <br /> <br /> <br />June 1964 storm, proved that the transposed latter storm could occur in early <br /> <br /> <br />June, although its maximum precipitation-producing effectiveness over the <br /> <br /> <br />project basin would be likely to occur earlier. The importance of the later <br /> <br /> <br />occurrence is that the most critical combination of storm rainfall and snow- <br /> <br /> <br />melt is much more likely to occur in early June than in May. This suggests <br /> <br /> <br />that the transposed maximized June 1964 storm, which was adjusted to May 23 <br /> <br /> <br />to 24 (line B, Table II-2), might be adjusted to about June 1. Since maximum' <br /> <br /> <br />dewpoints are rising in May and June, any adjustment of the storm to a later <br /> <br /> <br />date by means of dewpoints would result in increased rainfall at a time when <br /> <br /> <br />storm efficiency is decreasing. A solution to this problem was provided by <br /> <br /> <br />the May 1894 storm. <br /> <br />DAMES e. MOORE <br />