Corn earworm migration risks are predicted to return to the Plains and western Midwest by Wednesday night and Thursday morning as the next weather system develops in the northern Plains region and high pressure currently in the Plains moves back into the southeastern United States. South to southwest winds will initially focus on the Plains and western corn-growing region but over time should shift north and east into the upper Midwest and southern Great Lakes and eastern Midwest regions as well by the extended period.
Low corn earworm migration risks are in place across the Plains and western Midwest Wednesday night and Thursday morning, and then the risk area expands north/east into Minnesota, Wisconsin, Illinois, and Missouri by Thursday night and Friday morning. A Moderate risk is also in place across northern Oklahoma, Kansas, southeast Nebraska, southwest Iowa, and northwest Missouri starting Thursday evening and continuing into Friday morning as the weather pattern in combination with an increase in reported silking corn acres especially in Oklahoma and Kansas warrants a higher risk. As a cold front settles south by the weekend, winds are likely to weaken and thus only Low risks are in place mainly south of US 20 or I-80 and mainly across the western and central corn-growing region.