Corn earworm migration risks will be on the increase by the middle to latter portions of this week. A developing area of low pressure in the northern Rockies is expected to push east into the Northern Plains region as high pressure moves into the eastern corn-growing region and eventually into the eastern United States by mid-week. In between the two pressure centers south to southwest winds are expected to be rather prevalent and will increase with time as the pressure gradient increases. Precipitation near an eastward-advancing cold front may also serve as an area for insect drop-out as well. Low risks are in the forecast for tomorrow night and Wednesday morning across the Plains, western corn-growing region, and into the upper Midwest with the risk spreading east into the heart of the corn-growing region (Iowa/Illinois) by Wednesday night and Thursday morning. A Moderate corn earworm migration risk is predicted for this time period across portions of Missouri, Iowa, Illinois, and southwest Wisconsin for the potential of higher density flights due to a combination of an expected stronger corridor of winds and possible precipitation, and also the fact that some very early planted sweet corn crops are already starting to tassel especially in portions of Illinois so these growers should be on the alert for new migrants from the south. Otherwise, Low risks continue into next weekend especially across the eastern corn-growing region and also further west as the next low pressure system develops.