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Meteorology for the 1997 Flood Season caused by the southeasterly outflow was one process working to generate the quasi-stationary storm complex. The evening of July 28 produced copious amounts of precipitation throughout eastern Colorado; however, four extreme bulIseyes of precipitation are clearly evident from observer reports and from available NWS radar data. Three of these bullseyes occurred in northeastern Colorado (Fort Collins in Larimer County, northwest of Hudson in Weld County, and in Elbert/Lincoln counties). The fourth bullseye of extreme precipitation occurred in northeastern Bent County in a rural portion of the state. The atmospheric conditions present on July 29 were very similar to those seen on July 28. A quasi-stationary front of thunderstorms developed along the Front Range on the afternoon of the 29th. The front, however, was not as stationary as the one on the 28th and began to migrate toward the east. The storm complex continued to grow as it moved east, and it eventually dropped 14 to 15 inches of precipitation on portions of Logan and Morgan counties (Doesken 1998b). The evening of July 29 also produced large amounts of precipitation throughout eastern Colorado; however, three extreme bullseyes of precipitation are clearly evident from the observer reports and from the available NWS radar data. These bullseyes all occurred in northeastern Colorado (Sterling in Logan County, WeIdona in Morgan County, and near Hugo in Lincoln County). A' similar pattern of atmospheric conditions continued to develop throughout the next week or so, producing locally heavy rains in northeastern Colorado, the eastern plains, and southeastern Colorado. In researching the meteorology associated with the 1997 flood season, it appears that the northeastern portion of the state (north of and including Lincoln County) received a greater frequency of extreme precipitation bullseyes than the southeastern portion of the state. This observation was presented to meteorologist Matt Kelsch, who responded with the following statement (Kelsch 1998b): The State of Colorado does exhibit a slightly greater tendency for focused storm events along and north of the Palmer Divide. Frontal systems often slow down or stop along east-west ridges, such as the Cheyenne Ridge along the Wyoming border, the Palmer Ridge in central Colorado, and the Raton Ridge along the New Mexico border. In addition, the geographic upslope along the northeastern Colorado Front Range and High Plains appears to be greater than the corresponding terrain slope in southeastern Colorado, which creates an up-slope condition slightly more conducive to focused precipitation. d479/chap2.doc 08/12/98 2-3