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<br />rue: PMPtopics799summary.doc <br /> <br />y~-'- <br /> <br />July 21,1999 <br /> <br />6. HMR 52 was not developed using storms considered transpositionable to the <br />Cherry Creek drainage basin.. Whizt analysis (i. e. analysis vs opinion) has been <br />performed to demonstrate the HMR. '~2 is appropriate for use for the non-orographic <br />COmponent of PIYlP for the Cherry Creek location? (Tomlinson) <br /> <br />. No consensus is reached by the group. The NWS will examine a way to verify ,/ <br />this assumption <br /> <br />7. The most recent storm included in HfffR 55A analyses is 1978. Was a review of <br />more recent storms conducted to ~dentify significant rainfall events which could <br />influence the site-specific P...",,/P study? (Tomlinson) <br /> <br />Storm events are reviewed after they occur to determine if the event would have a <br />significant impact on the regional study. As of 1995, no storms were identified <br />that would alter Hi\1R5 5 A . ' <br /> <br />8. Table 14 in HfrfR 52 provides a list of the storms used to develop the withinlwithout <br />curves. Averages of values from these 29 storms were used and smoothed It is stated <br />that the authors of HfrfR 52 chose not to consider any regional variation that may e:x:ist <br />in these storm ratios. They additionally state that they consider this conclusion (i. e. not <br />to consider regional variations) to bejustified at this time (1982) but add "..., however, <br />future study should investigate regional variation in depth-area relations." In the <br />H},t/R 55A discussions related to Depth-Area-Duration Relations (Section 11), it states <br />that "...DAD relationships in the non-orographic regions west of the HMR No. 51 <br />. region should decrease with increasing area size at an even faster rate than they do <br />within the HfffR No. 51 region." In light of these identified variations west of the <br />HMR 51 region and the suggestion that future studies should investigate regional <br />variations in depth-area relations, why were not regional variations in the <br />within/without curves considered in the site-specific PJJP study for Cherry Creek? <br />(Tomlinson) <br /> <br />No consensus is reached by the group. The NWS will examine a way to verify A.,./ <br />this assumption <br /> <br />9. Among storm K-factors were applied to the within storm rainfall values to account <br />for orographic effects, in agreement with the 1lliR 52 recommendmion that additional <br />modification to the distributiqra of PMP brought about by terrain effects be considered <br />(Section 5.1, p43). However, HMR 52 states that these local modifications should <br />modify or warp the pattern in the direction of major storm patterns that have been <br />observed in the drainage. Does the application of the among storm K-factors modify <br />the pattern in the direction of major storm patterns that have been observed in the <br />drainage? Please provide examples. (Tomlinson) <br /> <br />No consensus is reached by the group_ The NWS feels that any additional study <br />results will have a minim~ J impact on results and there will be no further examination of <br />this issue at this time. <br /> <br />. ,Topics to 21 JIIiy 1999.TeduIical Meiting:.- , ,~_':, 2 <br />~:,,'~~".; ;~~~..:.:_~.~ :::.::...:::~~~ ::. - . ;.-:- ..2~:~'~~::':~;~~.:.~~:~::z:~;~ :'~.2-.~.{::~_::~'~:' <br /> <br />,- .- ..-. ~-- -~'.-. . <br />.-'. -.. . <br /> <br />..- ..". _. .._+". <br />:- .....;:_.:.._';.;;- <br />