Moths: Agrotis exclamationis (Linnaeus, 1758), Agrotis segetum (Denis & Schiffermuller, 1775), Xestia c-nigrum (Linnaeus, 1758), Lacanobia oleracea (Linnaeus, 1758), Mamestra brassicae (Linnaeus, 1758) and Autographa gamma (Lin- naeus, 1758) are members of the Noctuidae family, whose caterpillars cause significant damage to agricultural crops, although locally and irregularly. Prediction of harmfulness is difficult, despite the fact that the flight period of adults is monitored using light traps and the values of the lower developmental threshold and sum of effective temperatures (SET) are known. Data analysis from the years 2010-2020 revealed that using SET is, due to the course of the weather in the monitored period, problematic.