Heavy rain triggered flooding problems across Iowa, Illinois Minnesota and Ohio last week and over the weekend, creating headaches for farmers trying to get into the fields to harvest. With the deluge of rainfall hitting key areas of the Corn Belt, is this a sign harvest 2026 could be trademarked by wet weather and delays? BAM Weather says it will be a tale of two harvest stories this year: harvest delays in the West with more favorable conditions in the East.
It’s been a soggy September so far. The Iowa Mesonet shows areas of eastern Iowa, northeast Indiana, and central Ohio have already recorded their wettest September to date on record, with several crop reporting districts ranking in the top 10 wettest on record for the month so far. A pocket stretching across southeast Minnesota, southwest Wisconsin, northwest Illinois, and northeast Iowa has picked up more than 7 inches of rain.
An Ag Belt Divided and El Niño’s Impact
Griffin says when you look at the intense rainfall amounts over the past week, the “ring of fire” pattern is driving those heaviest totals.
“I think as we head deeper into harvest, it’ll be a bit of an Ag Belt divided. The Western Ag Belt’s gonna have some issues, the Eastern Ag Belt I think starts to get more and more favorable windows upcoming,” says Matt Griffin, Senior Vice President of Meteorology at BAM Weather.
Looking at precipitation totals before this past weekend’s rains, the heaviest bands included three-plus inches of rainfall stretched from near I-80 in eastern Nebraska into Iowa, just north of I-70 into Kansas, and across northern Missouri. Portions of northern Illinois, northern Indiana, and northeastern Indiana into northwestern Ohio picked up as much as 7.5 inches.
“I think a lot of this is due in part because of the strong and strengthening El Niño, where, in fact, we are barreling towards near-record levels,” Griffin says. “What a strong El Niño is doing is it’s essentially pumping in a lot of moisture from a strong subtropical jet. We’ve seen that through August and even bleeding into the middle part of September here, unfortunately.”
Heat Lingers in the South as Rain Continues in the North
Looking ahead, Griffin says the Eastern Ag Belt, especially toward the Great Lakes, will see a brief reprieve from the heat over the next two weeks, while the Southern Plains, from Texas down toward Kentucky, continue to deal with above-normal temperatures.
Warmth is expected to build back into the pattern heading into the final days of September, which Griffin says will also bring additional precipitation risk to the West.
“Precipitation in the next two weeks—the next seven days in particular—is pretty active from Iowa into northern Indiana and Ohio, with a lot of that coming through Sunday,” Griffin says. “Beyond Monday of next week, things do get a little calmer across the area. The problem is, some of the areas that have seen a lot of rain, and will continue to, it’s going to take time to dry out.”
Wet West, Drier East Into October
Griffin says the pattern into the final days of September and beyond into October will continue to feature a wet West and a drier East, which is a theme he expects to persist.
“Honestly, the best harvest conditions will be in the Eastern Ag Belt. But the further west you get, the wetter conditions will be,” Griffin says. “I’m concerned about South Dakota, Nebraska and Kansas, where harvest may be a bit of an issue. But even Minnesota through Iowa and Missouri, I think there can be enough rain chances there where it can be a little bit of a struggle—but not as bad as areas further to the west.”
For now, growers across much of the Corn Belt are left watching the radar instead of running combines. And while Griffin says the calendar will eventually turn drier, the divide this harvest season is clear: producers in the Eastern Ag Belt should find their windows widening in the weeks ahead, while those farther west, which includes from the Dakotas through Kansas and into Iowa and Missouri, may need to grab every dry hour they can get.