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<br />have definitely seen instances of very high dewpoint air behind summertime <br />plains cool fronts converging into the South Platte Basin. While most of your <br />arguments still hold for the PMP storms, I do feel there may be scenarios under <br />which leeside depletions would be little to none -- slightly lower dewpoint air, <br />perhaps, but with no orographic subsidence. You may address this in some of <br />your calculations and assumptions, but I'm uncertain, <br /> <br />4) Limiting the storms you consider to only Colorado storms has obvious benefits <br />(the question oftransposition becomes more manageable) but also introduces <br />some uncertainty (sample size too low and other very large storms from places <br />like Montana that may, in fact, be relevant, are not included). I have struggled <br />with this a lot. Had there been fewer Colorado storms to consider, then you <br />almost certainly would have chosen to look further, but because there have been <br />some very impressive storms very near Cherry Creek you did not feel the need to <br />look elsewhere. Would it make any difference to your outcome had you <br />considered some of the largest storms from eastern Montana or New Mexico? I <br />do agree that there would be no reason to transpose storms from areas east of <br />Colorado or use their areal reduction characteristics for application over Cherry <br />Creek. (P.S. The analysis of areal reduction of Colorado storms versus the <br />larger sample used for HMR 52 was an excellent contribution. I STRONGLY <br />RECOMMEND THAT YOU SUBMIT THAT ANALYSIS FOR <br />PUBLICATION IN THE HYDROMETEOROLOGICAL SCIENTIFIC <br />LITERATURE) <br /> <br />5) That being said, I have questions about your spatial analysis of precipitation you <br />showed for two storms that I am most familiar with. This could have some <br />bearing (probably small) on the results in number 4 above. For both the Fort <br />Collins and the Pawnee Creek storms, the isohyetal patterns that you show differ <br />in several ways from the maps that we drew. These differences were not <br />explained in your report but were quite noticeable. I assume that your maps were <br />drawn using actual observed data points and then applying the GIS objective <br />analysis tools to get spatial patterns. Our maps for those two storms also <br />included radar data to help interpolate over areas where data were not available <br />or in doubt, In both cases, the rainfall patterns you showed likely would have <br />yielded less precipitation than what our analyses indicated, at least near the storm <br />centers. We strongly believed that the radar data in combination with the point <br />measurements provided the best final product. <br /> <br />This then raises the question for the other storms, Did you reanalyze all previous storms <br />with your software or did you utilize the previously completed isohyetal patterns from <br />previous analyses? This is important to know. <br /> <br />6) Since this is a foundational piece of research and storm documentation, it is <br />imperative that all sources of information that you relied upon for determining spatial and <br />temporal patterns of rainfall from past extreme Colorado storms be extremely well <br />documented, Please specify clearly in your report exactly where you obtained this <br />