In 2019 — the 2nd wettest year ever in the U.S. — flooding cost Illinois and the Midwest $6.2 billion. Scientists predict more waterlogged days ahead.

Flooding on the Mississippi River and its tributaries throughout Illinois and the Midwest caused an estimated $6.2 billion in damage in 2019, the National Oceanic and Atmospheric Administration said Wednesday. The floods, which overwhelmed towns, farms, roads, bridges, levees and dams, contributed to the deaths of four people across 13 states.

The annual report comes as scientists reported that the U.S. continues to experience rising temperatures, and frequent, drenching rains are becoming more commonplace throughout the Midwest and the country. There is no immediate end in sight to these trends,...