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9) Phone searches. As information from all data sources was compiled, preliminary analyses were performed which then pointed out a few areas north and southwest of Fort Collins for which very few rainfall reports had been obtained. Special focused efforts were then initiated to identny possible data sources for those areas. Using personal contacts, irrigation companies, and a variety of referrals, additional rainfall reports were identified to help fill in data voids. 10) Supplemental Data-Radar (National Weather Service, CSU CHILL) At the same time that precipitation data were being assembled, contacts were made to obtain radar data from two independent meteorological radar sites: I) The operational WSR-88D National Weather Service weather surveillance radar located east of Denver, and 2) the Colorado State University CHILL research radar near Greeley. The use ofradar data will be discussed later in this report. The initial efforts were focused on e-mail, newspaper and radio announcements in order to collect data from as many sources as quickly as possible while evidence and memories were still fresh. Known sources of data such as National Weather Service official stations and cooperative observers for Mountain States Weather Services were not initially pursued, since it was assumed that these sources would be available in writing and would not require much follow up efforts. A special form was developed for recording each rainfall report (Appendix B). For each report received, a variety of information were obtained and recorded. . "Observer Information." The location of each measurement site was recorded, and information on how to contact the observer was noted. This was important since many observers were contacted two or more times with follow-up questions as the analysis proceeded. . "Rainfall Amounts." The observed rainfall totals were recorded along with any objective information about how that rainfall was distributed over time. Since the rain began Sunday evening (July 27, 1997), fell in several distinct periods, and culminated Monday night, many observers had time to read and empty their gauges more than once during the period. In fact, many gauges would have spilled and their readings would have been useless were it not for the great diligence of many individuals who took multiple measurements. While most reports were either a single total for the whole storm period or perhaps two separate measurements, some observers read their gauge and noted the measurement times as many as 10 times. Some got totally soaked in the process, but the resulting information made it possible to deduce the time history of the rainfa1l with good accuracy. . "Type of rain gauge." When interviewed, each observer was asked to describe the type of rain gauge they were using. This is helpful information in interpreting observations. Also, for many sites, especially those receiving heavy rainfall totals, more information about precise gauge location and exposure was obtained. . "Other Remarks/Information." Observers were asked to provide any additional supporting information either about their rainfall observations or about their storm 6