June runoff in the Missouri River Basin above Sioux City, Iowa was 3.3 million acre-feet (MAF), 60 percent of average. The updated 2025 runoff forecast for the Missouri River Basin above Sioux City, Iowa, continues to be below average.
“Mountain snowpack melted more rapidly than normal, and all reaches except the Sioux City reach experienced below normal precipitation during June. As a result, June runoff was less than forecast. Dry conditions are expected to continue in July,” stated John Remus. He is chief of the U.S. Army Corps of Engineers’ Missouri River Basin Water Management Division.
The 2025 runoff forecast above Sioux City is 19.1 MAF, 74 percent of average, and slightly lower than last month’s forecast. It is based on current soil moisture conditions, mountain snowpack, and long-term precipitation and temperature outlooks.
