The following content was provided by meteorologist Gail Martell of MartellCropProjections.com:
Hurricane Rainfall Beneficial, Too Late For Most Soybeans
Hurricane Isaac delivered heavy soaking rain to the lower Mississippi Valley and Eastern Midwest, improving soybean prospects, though the rain came too late in the soybean pod-filling stage for the maximum yield benefits.
Central Illinois received up to 3.7 inches of rainfall, more than the entire monthly allotment for August. Mississippi Delta farms in Arkansas, Mississippi and Louisiana received nearly 4 inches of rain. Missouri, a state hit hard by summer drought, received 2.75 inches of rain.
Late summer rainfall is highly influential in determining soybean yields, affecting pod setting and seed-filling. The size of developing seeds is strongly impacted by August rainfall. Soybean farms that received good August rainfall (mostly east of the Mississippi River) may see a higher soybean yields on the new soybean report. West of the Mississippi River, the yield outlook is poor.
On balance, conditions are worse in soybeans than a month ago, not only due to the distribution of rainfall but also because of late-arriving hurricane rains.