So, Do Ya Think It'll Rain?

In a typical year, and this one is certainly not an example of typical, farmers are vexed when it rains on the other side of the road, but not on their field. When your crop needs rain, and the neighboring field gets a "million dollar" shower, that is a reason to ask why? Mike Tannura remembers when his father told him how it could rain on one side of the street, but not the other, when he was growing up in a Chicago suburb. Whether it was a paved street or a rural road made no difference, but the fact that raindrops had to stop somewhere fascinated Mike and eventually brought him into the world of agriculture.

You may have seen him on WCIA or WILL television, and thought, as I did, this fellow knows as much about the weather as the late, and still revered Channel 3 weather forecaster "Mr. Roberts." After his Iowa State University degree in meteorology and a brief TV fling in Hastings, NE, and Champaign, IL, Tannura received a graduate degree at the University of Illinois focused on the impact of favorable and unfavorable weather on crop yields. His weather maps are now plotting weather systems that can forecast agricultural profitability, based on temperature and precipitation patterns around the US Cornbelt, and in South America.

This is where the rubber meets the road, or shall we say raindrops on the road. Tannura and his economist colleagues looked at weather data and crop yields as far back as 1960, when nitrogen came into common use and substantially increased yields. There is no question that corn hybrid genetics have allowed yields to rise, but what impact has the weather contributed? Tannura says based on the bad weather years of 1974, 1983, 1988, and 1993, and 1995 it is apparent that bad weather pulls yields down farther than good weather boosts yields upward.

The next step in the research is to analyze the past 10 years, when there really have not been bad weather years such as those previously mentioned. Tannura says it is possible to see yields working higher than the trend line because bad weather was just not happening. He says he's not a farm boy, and does not really understand the process of farmers making their seed decisions. But he says he does know that yields are improving and the weather cannot be discounted as a positive factor in that trend.

In the middle of the growing season, Tannura's research can be applied by farmers who are implementing their marketing plans, well before the crop is harvested. Using a variation of his weather models, last July, University of Illinois agricultural economists Scott Irwin, Darrel Good, and Tannura forecast a 12 billion bushel corn crop, which turned out to be 12.1 billion. Anyone following his recommendations would have close to the bull's eye on the crop production target.

Tannura may not yet be a familiar name in many machine sheds, but through his company "T-storm Weather", the members of his growing clientele on the Chicago Board of Trade depend on his weather forecasts to make money or save money buying and selling commodities. He says it is difficult to pinpoint whether it will rain on a given farm or in a given county, but across a wide area he's alerted his subscribers about the increased rain in Iowa, Illinois and Indiana, and a major heat wave in the southern US that could be a problem for soybeans in Arkansas and Louisiana if it lasted into July.

That latter information is also valuable to Midwest soybean producers, because heat is unfriendly to Asian soybean rust, and a blistering summer in the Mississippi Delta could be a barrier to rust spores that need cloudy, cool, and moist conditions to make any northbound journey.

That is all well and good, but just make it rain on the right side of the road.