Fall weather outlook

Iowa crops are teetering precariously on a see-saw of whether or not they will be able to finish maturing in time for harvest.

That’s according to Bryce Anderson, senior ag meteorologist with DTN.

Cool temperatures during emergence this past spring, followed by drought and near-drought conditions from mid-July to mid-August, cooler late summer temperatures and the worry about when the first killing frost will occur bring him to this point of concern.

“This has been a tricky, frustrating year,” said Anderson. “… and I think we’re not going to get out of it quickly.”

He said he doesn’t think an early frost is likely, but added that first 32-degree frost could result in corn dryers running more, along with a possible loss in production.

Anderson said planting was held up by two and a half weeks this year because precipitation was above normal in the northern and eastern Corn Belts.

“We know there was a lot of replanting that went on in the eastern Corn Belt, but in the northern Midwest, planting was about two to two and a half weeks later than it has been in the last two or three years,” he said. “It ripples through the rest of the season, and now we come to the end of it with the questions being whether we will have enough time to bring crops along.”

Anderson said weather information from USDA and the National Oceanic and Atmospheric Administration indicate that growing degree day totals over much of the northwestern half of the Midwest are anywhere from 100 to 200 growing degree units behind average.

He spoke of a south central Minnesota farmer whose crop was planted two and a half weeks late because of rain and cool conditions.

“By the end of September, at that location (and with the corn hybrid he’s using), the growing degree totals by the end of September will be just short of full maturity, and that puts the crop into a precarious situation because in the northern Midwest, you get that first frost right around that late September/early October time frame,” Anderson said.

He added that even with a normal first frost occurrence, planting delays due to cooler temperatures and temperatures in late summer running 10-15 degrees below average could result in crops not reaching full maturity.

“This is the most difficult situation we’ve had for the end of the season for 10 years, because we’re going back to 2009 to find any kind of comparable scenario, in the western and northern Midwest in particular,” said Anderson. “Even with that, this year is not as extreme as that year was with the kind of harvest delays we saw then.”

Anderson said if crops cannot completely reach maturity, the impact could be higher moisture content at harvest time, issues with grain dry-down in the field, more use of grain dryers and higher propane expenses.

“I know of growers who have gotten a larger amount of propane inventory laid in than they have over the past three years because of the way things are panning out at the end of the season,” said Anderson.

He added there are pockets around the Midwest that have been very dry during July and August and said when grain weights could be disappointing.

“Much of Iowa, northern Missouri and Michigan had rainfall from mid-July to mid-August that was 75 percent or more below normal, and even in parts of Illinois and Indiana there were parts of those states that were very dry too, particularly south central Indiana,” Anderson said.

The dry component can’t be ignored.

“It’s the driest in Iowa since 2012, when we had the tremendous drought across the Corn Belt,” said Anderson. “There has been some impact in terms of yield prospects, especially in south central Iowa, where most of the dryer conditions are most prominent.”

Anderson said there is neither a La Nina or El Nino in effect currently and that the Pacific Ocean is in an inactive phase. He said it’s likely there will not be a La Nina develop over the winter.

For now, he said there is a good chance that fall weather will feature mild temperatures and average rainfall overall.

That being said, he predicts the drought in the Dakotas will remain through the winter and the Northern Plains area will go into the spring of 2018 with a more dry profile.

“It will cause concern for a number of months, after it has already effected crops in the Northern Plains during this season,” said Anderson.

He added Midwest weather pattern expectations show above normal temperatures and normal precipitation, while the Northern Plains show above normal temperature and below normal precipitation.

“The big concerning time period will be with the transition from summer to fall,” Anderson said. “If we can get through the scenarios in September and get crops to that final maturity stage, I think the harvest will treat us fairly well.”