Corn Earworm
A predominantly northwest to southeast flow weather pattern is predicted to continue for this week for much of the corn-growing region. As a result, corn earworm migration risks remain none or Low, and are mainly tied to low pressure systems that may result in some south to southwest winds ahead of trailing cold fronts. Corn earworm moth populations are increasing across source regions in the mid-south and crops in that area are becoming less attractive to active moths, so even subtle southerly wind events may lead to at least isolated moth flights into portions of the corn-growing region this week. Low risks are in place ahead of a low pressure system expected to develop in the western Plains by tomorrow. Fields mainly south of US 20 and west of US 65, or from Nebraska and Kansas east into western Iowa and western Missouri are at risk tomorrow night into Wednesday morning. An additional Low risk is in place from Kansas and Missouri northeast into eastern Nebraska, Iowa, southern Minnesota, southern Wisconsin, and into Illinois by Thursday and Friday nights as a low pressure moves near the Canadian border with a cold front trailing to its south. South to southwest winds are likely ahead of this low pressure but are not predicted to be overly strong. These winds, however, could originate in active mid-south source regions, especially to the west of the Mississippi River, so at least Low risks are warranted at this time. Despite a somewhat unfavorable weather pattern for migration, growers with crops at risk should continue to monitor traps as some local flights could occur in the next week.