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<br />, <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />NWS 11 May 2001 <br /> <br />9. Among storm K-factoro were applied to the within storm rainfall values to account for <br />orographic effects, in agreement with the HMR 52 recommendation that additional <br />modification to the distribution of PMP brought about by terrain effects be considered (Section <br />5.1, page 43). However, HMR 52 states that these local modifications should modify or warp <br />the pattern in the direction of major storm patterns that have been observed in the drainage. <br />Does the application of the among storm K-factors modify the pattern in the direction of major <br />storm patterns that have been observed in the drainage? Please provide examples. (Tomlinson) <br /> <br />The group did not reach consensus. The NWS opinion is that any additional study results <br />will have a minimal impact on results and there will be no fUrther examination of this <br />issue at this time. <br /> <br />Answer 9. <br /> <br />No response needed. <br /> <br />10. The barrier elevation map in HMR 55A was used to adjust the raster fields of <br />"non-orographic" values to sea level. Was this map also used for its intended purpose (i.e., <br />moisture depletion)? (Tomlinson) <br /> <br />The group agreed this question was answered. HMR 55A PMP values included moisture <br />barrier depletion. <br /> <br />Answer 10. No response needed. <br /> <br />11. The BOSS software package has demonstrated errors in its calculation of within storm <br />isohyetal values (personal communication, Ellen Faulkner, Mead and Hunt Engineering, June <br />1999). The software sometimes produces rainfall volumes larger than the PMP for areas <br />smaller that the PMS (Probable Maximum Storm). Were tests conducted to demonstrate that <br />this error did not occur? (Tomlinson) <br /> <br />No longer applicable according to Dr. Tomlinson. <br /> <br />Answer 11. No response needed. <br /> <br />12. The chronology for the temporal variations were based on hourly percentage contributions <br />from HMR 52. Were these variations derived from the same 29 storms used to derive the <br />within/without storm curves in HMR 52? How do they compare to the largest storms which are <br /> <br />11 <br />