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<br />7: Barrier Effects of Monument Ridge. <br />8: Wind Speed and Storm Movement Patterns. <br />9: Spatial Distributions of the Storm Centers. This analysis will concentrate on spatial <br />distributions of historic storms which have occurred along the Colorado Front Range and <br />compare them to storms used in the spatial distribution computations in HMR 52. <br />The results of these sensitivity analyses will be presented in a logical manner which <br />addresses the individual sensitivities of each of the variables and also will address the effects of <br />various combinations of these variables. A concise summary of the sensitivity will be provided. <br /> <br />Task 4 <br />An interim report will be prepared which will summarize the conclusions from Tasks 1-3. <br />The results will be provided to the technical review panel at a review meeting. <br /> <br />Task 5 <br />The site-specific PMP study will be primarily based on historic extreme rainstorms, which <br />have occurred over locations which are topographically and climatologically similar to the <br />Cherry Creek drainage basin. The primary reference document to be used for identifying the <br />most extreme storm events will be the Colorado State University summary of extreme storms in <br />Colorado published in 1997. In addition, A W A will conduct data searches to identify other <br />extreme storms, especially those occurring since 1997. Data for each of the variables evaluated <br />in Task 3 will be identified and procured from various agencies with archived storm data. These <br />agencies will include but not be limited to the Bureau of Reclamation, National Weather Service <br />and the Colorado Climate Center. Available radar data will be collected for use in determining <br />the isohyetal shapes of historic large rainfall events over the basin, the orientation of the <br />isohyetal patterns and the positioning of the rainfall centers over the watershed as well as <br />eval uating the temporal characteri sti cs of the rainfall. <br />Historic techniques employed in the HMRs will be used to maximize and transposition these <br />storms over the Cherry Creek drainage basin. Historic storm analyses will be reviewed. Storms <br />will be re-analyzed if any problems are identified. The hydrologic evaluations being conducted <br />by Flow Technologies (discussed below) will assist in this effort. For example, HMR 55A <br />shows how the storm representative dewpoint associated with the Cherry Creek 1935 storm was <br />determined. Dr. Tomlinson showed in the July 1999 technical meeting in Denver that the <br />dewpoint data used in that analysis is incorrect since it was observed over 500 miles away from <br />the rainfall event during the same period of time that the extreme rainfall was occurring. The <br />storm representative dewpoint for this storm will be re-evaluated and the storm maximization <br />factor recomputed. <br /> <br />There has been disagreement for many years over the acceptance of the rainfall observations <br />used in the Cherry Creek 1935 storm isohyetal analysis, mass curves and depth-area-duration <br />curves. As a tool to access the reliability of these analyses, A W A proposes to have Mr. Doug <br />Trieste of Flow Technologies apply the USACE HEC-l model to estimate the Cherry Creek <br />