Preharvest sprouting (PHS) has been recognised as the primary cause of low falling numbers (FNs) in wheat. From recent research it is clear that there are a number of additional causes of low FNs, including late maturity alpha-amylase. FNs of certain cultivars have varied considerably from year to year and across environments in the wheat producing areas of the Free State Province. In this study we aimed to determine whether climatic conditions could contribute to unexpectedly low FNs. Eleven cultivars were planted over a 5 year period in five different locations in the Free State Province. Total rainfall, minimum and maximum temperatures and growing degree days were determined during six environmental periods. Results from this study indicated that rainfall during the later stages of grain filling and grain maturity had a negative effect on the FNs of 7 of the 11 cultivars, while maximum temperatures during these growing periods were positively correlated with FN in 8 of the 11 cultivars. Minimum temperatures just prior to harvest could also determine the FNs of certain cultivars. Principal component analysis identified three groupings of cultivars varying in the frequency of low FNs experienced over the 5 years of the study. It is clear from this study that rainfall just prior to harvest, and therefore PHS, was not the major factor responsible for the low FNs obtained during this study.