The Mississippi River is at risk of bottlenecks for a third straight year as warm, dry spring weather and low winter snowpack limit the amount of water feeding into it, according to the National Oceanic and Atmospheric Administration (NOAA). 

The U.S. will get warmer-than-average spring temperatures from April through June, and for the first time since 2021 there is no region at risk of major flooding, according the agency’s Spring Outlook report issued March 21. Drought conditions are expected to persist or worsen across parts of the Great Plains and Rocky Mountains. 

More than a trillion pounds of freight per year travel on the Mississippi and the rivers that flow into it. It’s a critical transport route from a region that produces 92% of U.S. agricultural exports. But the waterway, like other vital trade conduits including the Panama Canal, is increasingly vulnerable to climate change.

Low flows on the Mississippi “could have potential impacts on those navigation and commercial interests that depend on water” from the river, Ed Clark, director of NOAA’s National Water Center, said in a statement. 

Still, NOAA experts stressed that it’s not certain what will happen with Mississippi water levels later in the year and that conditions need to be monitored over the next several months.