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<br />" <br /> <br />Specific comments regarding task 3 are: <br />L Pages 8-13: A lot of what is being inferred here regarding the positioning (time of occurrence) <br />of the NWSSS PMP maximum hourly peak rainfall arid/or large rainfall amounts surrounding the <br />peak as depicted by what is shown on page 9 of the A W A interim report compared to observed <br />storm precipitation really becomes a mute point if one realizes that NWS isn't saying in running <br />the HMR52 computer program that this is the realistic and only time position of the peak burst of <br />rainfall. Hydrometeorological Reports (including HMR52) typically provide a whole variety of <br />sequencing increments of precipitation but without indicating the time of day the peak <br />increment of rainfall should occur.. For instance, the peak hourly value from the NWSSS study <br />is placed at 10 pm and that run by A W A places the peak value at 4 am both not supporting the <br />statements made on pages 8-13. The user has basically control as to where 'he places this extreme <br />increment. One shouldn't use the placement shown by either NWS or A WAin this report for <br />making comments about the PMP storm's validity. It is either just a default setting or that <br />selected by an individual to merely process the data and in many cases is not a true <br />representation of what can happen in nature. I do recommend that A W A pursue the development <br />of a more realistic storm sequence. Your item I on page 11 and the results indicated on page 9 <br />(figure), supports this development if pursued. I see in general a impact on peak flow but not <br />necessarily on volume. <br /> <br />2. Page 10: Need a better figure to indicate your point. <br /> <br />3. Page 11, paragraph I: Mr. Leversoo. did not draw the mass curve. He used the original <br />provided by the Corps of Engineers storm study for the May 1935 event. <br /> <br />4. Pages 14-20: Most interesting section under task 3 in my opinion. Has the greatest potential to <br />make an impact on PMP storm flood results and stay within the general criteria described for <br />developing PMP estimates as indicated in both the WMO manual and the Hydrometeorological <br />Report series. Encourage A W A and others to explore/develop thoughts and findings of what is <br />indicated here. We need more storm data or other types of information here to indicate support <br />for what your trying to investigate. Radar data should help and perhaps atmospheric storm <br />modeling can add to the evaluation. Would and have suggested that and applications manual <br />similar to what HMR 52 does but for total orographic regions be developed but never was given <br />the money to move forward. <br /> <br />5. Page 14, paragraphs 2 & 3: Am I missinga figure here or is the same figure in the last two <br />sentences in paragraph 2 the same one being used in paragraph 3? ' <br /> <br />6. Page 14, paragraph 4: Need more justification for your use of the "missing Cherry Creek <br />storm" as shown in this configuration. Why couldn't it be shifted slightly more one way or the <br />other to provide a better fit. Same for your paragraph at the top of page 18. <br /> <br />Additional CWCB Summary Comments: <br />I believe that A W A has met the minimum requirements for this section to date. They will, I <br />hope, add in the draft final report some measure of the impact some of these items will have on <br />the flood results that is obtained. Would provide a better indication where the biggest bang for <br />