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at Brownville, Nebraska, was more than 4.5 feet above flood stage. Based upon data collected at the Missouri River gage at Nebraska City, Missouri River flows likely approached 100,000 cfs at the mouth of the Nishnabotna River, while that river was near peak stage. J The peak stage of 33,2 feet reached by the Nishnabotna River at Hamburg gage set a new record stage at this station. This exceeds the previous record flood stage of 30.56 feet set on 25 July 1993. Station records go back to 1923. Since the final discharge estimate is not available yet, a frequency has not been assigned to the flood. Based upon the discharge measurement made at Riverton, the flood definitely exceeded the 1 DO-year event, ; Flooding continued on the lower Nishnabotna River and the Missouri River from Nebraska City downstream through the end of June, as flood water returned to the channel from flooded fields. Thunderstorms continued to pound other parts of the District as a cold upper-level storm system moved from the northern Rockies onto the northern Plains. Heavy rains of 2.5 to as much as 5 inches fell in northeast Nebraska and in the Dakotas on June 17th and 18th resulting in some lowland flooding, particularly on Shell and Beaver Creeks west of Columbus, Nebraska. Reservoir elevations in the Black Hills rose in response to runoff from those storms. Snow accumulated in the high mountain passes from Colorado through Montana. Minor flooding was also reported in the Beaverhead River basin of Montana, due to above normal rainfall and seasonal snowmelt on the 19th. (5) Early Summer 1998. , Widespread thunderstorm activity returned to the northern plains by June 23'd, as thunderstorms developed north of an upper level high-pressure ridge centered over Texas. Thunderstorms became more numerous along the Front Range as the circulation around the high-pressure system set up a monsoonal moisture flow in eastern Colorado, Wyoming and Montana. Two to four inches of rain fell in the South Platte River basin northeast of Denver on the 23'd, with tornadoes and hail reported in Wyoming and several locations in Nebraska. Flash flooding was reported along small streams in northwest Iowa and northeast Nebraska on the 24th. Minor flooding occurred along Pebble and Maple Creeks northwest of Fremont, Nebraska, the Boyer River near Denison, Iowa, and the West Fork Ditch near Hornick, Iowa. The Missouri River pushed above flood stage at Williston, North Dakota, and the Cheyenne River rose to near flood stage at Cherry Creek, South Dakota, , Montana became the focus of storm activity by June 26th. Two to 4 inches of rain added to receding snowmelt runoff and caused flooding of minor streams near Dillon and on the Ft. Belknap Indian Reservation. Continued rain caused larger 15