Warm February temperatures triggered early snowmelt and runoff in the Missouri River Basin above Sioux City, Iowa, but the overall 2026 runoff forecast remains well below average.
February runoff was 1.3 million acre-feet, 113 percent of average. Despite this above average runoff in the Garrison, Oahe, and Gavins Point reaches, the full-year runoff forecast above Sioux City, Iowa is 20.6 MAF,