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7 HMR 55A is about 4 percent at 6- to 72-hours if the precipitation during these durations is considered non-orographic, and from 14 to 18 percent if it is considered orographic. Larger percentage reductions than these are found at 1-hour, in line with the behavior of the HMR-52 technique evidenced in basin studies for slightly smaller drainages in the eastern united states such as those reported in NOAA Technical Memorandum, NWS HYDRO 39, "Probable Maximum Precipitation for the Upper Deerfield River Drainage in Massachusetts/Vermont," Silver Spring, Maryland, 1984 and NOAA Technical Memorandum, NWS HYDRO 41, "Probable Maximum Precipitation Estimates for the Drainage Above Dewey Dam, Johns Creek, Kentucky, Silver Spring, Maryland, 1985. '" t,. In Figures 2-5, the isohyets are seen to converge into a single line outside of and mostly surrounding the Cherry Creek Drainage boundary. These so-called "concurrent" values may not be fully accurate everywhere and they should not be used for any hydrologic application. It is cautioned that the average 10-mi2 depths shown in Table 1 for sea level are NOT comparable with values from Figure 29 of HMR 52 or Figures 18, 20, or 22 of HMR 51, especially along the coastline of the Gulf of Mexico. These Figures may also been found in Appendices A and C. The values in Table 1 are to be regarded as temporary expedients, accurate in their own right, toward the goal of calculating within-storm depths of PMP at a common elevation as required for HMR 52. These calculations could (just as well) have been performed at some other elevation either below or above the barrier elevations of the Cherry Creek Drainage. Furthermore, the choice of a pseUdo-adiabatic lapse rate for adjusting average, 10-mi2, among-storm depths from the Cherry Creek Drainage to a common elevation was arbitrary. What matters in this case is that the inverse of the adjustment that "brought" values from one level to another is used to "return" them to their original elevation. The cautionary comments of paragraph 8.4.2.2 of HMR 55A ("We noted that the atmosphere produced equal magnitudes of rainfall in the May 31, 1935 Storm at Cherry Creek (6,900 feet) and at Hale (4,000 feet). Our concern. . . in transposing to lower elevations led us to adopt a change to previous studies. In this study, we make a consensus decision . . . to control unrealistic maximizations in general storms.") are the basis for the present concern that the values of Table 1 in this study not be compared with among-storm values from other reports. Neither is it correct to infer that because the values of Table 1 are larger than values from other HMR's, the values from Plates Ib-IVb from HMR 55A in the Cherry Creek Drainage are too \.