Shift in Weather Plans

July could go out cooler, wetter than normal. Tom J. Bechman

Published on: Jul 21, 2004

Earlier in the spring, Jim Newman's crystal ball was hazy for July and August. If anything appeared in the ball at all, it leaned toward warmer and drier, especially for the southern half of Indiana, and warm with normal moisture, whatever normal is, for the rest of the state, and for most of the Corn Belt.

Then a wet spell developed beginning in mid-to-late May. Newman, and independent ag climatologist, West Lafayette, Ind., still expected a switch back to warmer, drier weather in early July.

However, that didn't happen, at least not over a widespread area. Some places within Indiana are experiencing short bouts of dry weather, but that's a common occurrence every year. Summer thunderstorms never drop rainfall equally over broad areas. Most parts of Indiana, however, have worried about too much rain, at least for getting fieldwork down, instead of too little, at least so far.

Now Newman expects the cool, wetter than normal spell to continue on through July. Coupled with the large percentage or corn that went into the ground very early this spring, both in Indiana and across the Corn Belt, he figures that a high percentage of the corn crop will be through its critical pollination period before weather conditions turn more stressful.

The result is the potential for a record or near-record corn crop nationwide, Newman reports. His latest numbers ran through the crop model he uses to make crop size projections led him to a national corn crop around 10.5 billion bushels.

It's still too early to say much about the potential impact of weather on soybean yields and total U.S. soybean crop size, Newman says. Soybeans, even this year, will be into their critical period for reproduction in August, not July. Should conditions turn to warm and dry, the risk of impact on the soybean crop would go up.

Other variables also remain unknown on soybean production. Last year, soybean aphids reached such high numbers that they knocked yields in some locations, sometimes by up to 20%. Aphids have been relatively quiet in soybeans so far this summer, but that situation could change quickly. Once aphids set up shop, their population can explode rapidly.

Stay tuned to your local extension office newsletter or Web site for news about soybean aphids.