Historic September Rainfall Delays Harvest & Manure Application
Relentless September rainfall is creating an increasingly difficult start to fall across Iowa and portions of the Midwest, leaving fields saturated just as corn harvest, manure application and other time-sensitive farm work are beginning.
In Iowa, the numbers are already historic. State Climatologist Justin Glisan said western Iowa was tracking among its five wettest Septembers in 154 years of records, while central Iowa ranked in the top 10 and eastern Iowa in the top 20 as of Sept. 18. Some locations have already established September rainfall records.
Des Moines provides one of the clearest examples. Through Sept. 20, the Des Moines airport had recorded 11.88 inches of precipitation for September, according to Iowa Environmental Mesonet data. The standing September record is 14.81 inches, set in 1914.
That means the 1914 record remains intact for now—but with more than a week remaining in the month, 2026 has already become an extraordinary weather year.
Wet Fields Collide With Harvest
During the week ending Sept. 13, Iowa farmers had only 4.5 days suitable for fieldwork, two fewer than during the same period last year. Just 2% of Iowa corn had been harvested, while 38% had reached maturity. Iowa’s statewide weekly rainfall averaged 2.05 inches—more than double the normal 0.84 inch—with some weather stations receiving 400% to 600% of normal precipitation.
Soggy fields could keep combines parked and that continued wetness and high dew points may also increase challenges for farmers with harvesting crops and field work.
For livestock operations, including pork producers, delayed corn harvest can have effects beyond the grain field. Harvest and fall manure application often compete for the same narrow window of favorable weather, equipment and labor.
Pork Producers Watching the Forecast
The rainfall is arriving during one of the busiest logistical periods of the year for Iowa agriculture. Corn and soybean harvest, manure hauling and application all depend to varying degrees on field and road conditions.
Iowa’s September-October harvest proclamation is currently allowing qualifying trucks hauling agricultural commodities—including corn, soybeans, manure and distillers grains—to operate at weights of up to 90,000 pounds on eligible Iowa highways without an overweight permit through Oct. 10, subject to the proclamation’s restrictions.
There is one positive side to the moisture: September rainfall has helped alleviate drought conditions in portions of western Iowa. Iowa Agriculture Secretary Mike Naig said the wet start to the month had helped ease drought but warned that continued rain could limit fieldwork.
For now, farmers across Iowa are doing something generations before them have done during difficult harvest seasons: watching the sky and waiting for the fields to dry.
And in 2026, September is giving farmers plenty to watch.
[author] [author_image timthumb=’on’][/author_image] [author_info]Rachel Fishback | Pork Industry News[/author_info] [/author]
Sources: Iowa State Climatologist Justin Glisan, Iowa Department of Agriculture and Land Stewardship, National Weather Service/NOAA, Iowa State University Extension and Outreach, and Radio Iowa. September 2026 totals and rankings remain preliminary until the month concludes.
