Under these conditions, the opportunity for crop injury at any specific off target site is very small because the pesticide is dispersed and diluted into the atmosphere. However, other problems may arise when the atmosphere is very stable. Under stable conditions, a warm air layer at some distance overhead may become a blanket, holding down cooler air underneath. Particles suspended in the cool layer cannot move anywhere except laterally, possibly for several miles. Inversions are part of a daily atmospheric cycle, occurring in the early morning hours when the ground cools the air layer immediately above it.
Inversions tend to dissipate during the middle of the day when wind currents mix the air layers.
Applicators concerned about these adverse spray conditions should wait until late afternoon or early evening to spray, when there is less chance of the atmosphere being inverted and conditions are more favorable. Atmospheric inversion usually occurs early in the morning. Atmospheric inversion can result in drift damage miles from the target area. If these particles are not in the spray emission, this weather-related phenomenon can be ignored.