Cordt Holub floated a kayak into a soybean field last week after heavy rains pounded parts of eastern Iowa, causing creeks to jump out of their banks and forcing neighbors to move cattle to higher ground.

“We’re looking at almost 8 inches of rain from (June 18-22),” said Holub, a Tama County Farm Bureau member.

Meanwhile, farmers in southwest Iowa reported crops were starting to show moisture stress last week after receiving less than 50% of their normal rainfall in June. 

The east-west divide has been particularly notable this year, said Justin Glisan, Iowa Department of Agriculture and Land Stewardship state climatologist. The national drought monitor shows abnormally dry conditions creeping into more than 20 counties in western Iowa. By contrast, significant river flooding is expected in eastern Iowa, where June...