El Nino & corn yield potential
It's likely going to be warmer than average, but the mercury likely won't top out as high as last summer. That's the assessment of the meteorologists at MDA EarthSat Weather, a Gaithersburg, Maryland-based weather forecasting firm. So, specifically, how will things shake out between now and fall?
It's important to recognize what's behind the change in conditions; MDA energy manager and meteorologist Travis Hartman says the southern oscillation index (SOI) -- a measure of ocean temperature and movement -- points to a shift from La Nina, the overriding system over the last 2 years, back to El Nino. The latter is typically characterized by warmer central Pacific waters and "reduced heat content in the Atlantic ocean compared to recent spring and summer seasons.
"Nationally, the summer of 2012 is expected to be slightly warmer than both the 10-year and 30-year normals, but measurably cooler than both the summer of 2011 and the summer of 2010 thanks to lessened heat expectations over the South, Midwest and East," Hartman says.
But, just because La Nina may be ending doesn't necessarily mean El Nino is a sure thing in the near future, says Iowa State University ag meteorologist Elwynn Taylor. And, with where the Corn Belt's moisture situation stands in most areas, it will be moisture, not temperature, that dictates crop potential moving forward.
"The end of La Nina is likely by May, but the outlook on the chance of El NIno is vague," he says. "Soil moisture seems to be the wild card for Midwest crops."
So, what's that mean to crop potential? A move away from a La Nina system "increases the possibilty of an above-trend U.S. corn crop in 2012," Taylor adds. Weighing all the factors, he says the odds are around 60% that La Nina switches to El Nino.
Hartman expects the summer to unfold this way:
9th warmest June since 1950
21st warmest July since 1950
16th warmest August since 1950