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<br />appear with the table in Appendix B. Some of these storms have already been studied in <br />detail. <br /> <br />Large precipitation reports that are potentially significant to the design of high elevation <br />dams and spillways but which appear totally or partially erroneous present serious <br />problems in the analysis of extreme precipitation. Verification or disapproval of the <br />validity of precipitation observations is a difficult process requiring detailed <br />meteorological information and also local str~ow records. By associating properties <br />of storms (area, intensity and duration) to ob~erved runoff and streamflow conditions, <br />validity of storms can be assessed. Results of selected storm evaluations follow: <br /> <br />There is considerable evidence that suggests that the Gladstone storm of October 1911 <br />was a major and legitimate large storm. However, the local report of over eight inches of <br />rainfall in 24 hours was considered questionable by several who have investigated that <br />storm in detail. Reports of flooding were not consistent with widespread heavy rains of <br />that magnitude. While the majority of committee members reviewing the storm doubt the <br />validity of the individual Gladstone report, it is possible it could have occurred over a very <br />localized area. <br /> <br />There is scientific agreement that several large rain reports during the 193 Os from <br />Leadville, including a 4.25" report in less than one hour in July 1937, were all inaccurate <br />due to unrepresentative precipitation measun~ment methods which included the use of a <br />special device for wind protection and improving winter snow catch that may have <br />enhanced summer rainfall. <br /> <br />A recorded 5.25 inch rainfall in a short period at Cimarron in June 1952 appears to be the <br />result of a gauge reading error by the observtr. During a period of several years, a <br />number of similar large daily precipitation amounts were reported by the same observer, <br />suggesting a pattern of observational errors. Other reports included 3.60 inches on <br />September 21, 1952 and 6.00 inches reporte<i January 20, 1962. When these values were <br />divided by 10, the Cimarron readings then Wtre very consistent with reports from <br />surrounding locations for each of those stOffils. In addition, there was no evidence of <br />flooding associated with the June 1952 stoffil. <br /> <br />Most recently, a large high-elevation rainfall report of more than 4 inches in one day in <br />August 1995 at the WoIfCreek Pass IE cooperative weather station was investigated <br />within a month of its occurrence. Again, imj)roper manual rain gauge measurement <br />procedures resulting in a factor of ten magnification were likely to blame. A substitute <br />observer took the observation that day who may not have known proper procedures. The <br />substitute observer was not available for comment. A remote automated precipitation <br />gauge was operating within approximately one mile of that station and reported 0.40 <br />inches. A team of USGS scientists were also in the area at that time. There was no <br />evidence of erosion or high stream flows anywhere in that area that day. Because the <br />storm was investigated quickly, the value was edited prior to digital archival at the <br />National Climatic Data Center. However, anyone utilizing the original hand-written <br /> <br />9 <br />