September precipitation was well-below normal in the Missouri River Basin. As a result, September runoff in the upper Missouri River Basin above Sioux City, Iowa was 69% of average. Since January 1, precipitation in the upper Basin is well-below normal. The National Weather Service’s Climate Prediction Center (CPC) is forecasting that below-normal precipitation will continue in October. The 2020 calendar year runoff forecast for the upper Basin, updated on October 1, is 30.2 million acre-feet (MAF), 117% of average. Average annual runoff for the upper Basin is 25.8 MAF.