The start of the rains is defined as the first occurrence of a specified amount of rain within two successive days. The probability distribution of the date of the start of the rains is derived from the rainfall models of Stern (1980a). The probabilities of occurrence of dry spells are used to define an earliest practical starting date. Results are presented for eleven stations on a N-S transect in West Africa. The variation in starting date with latitude is described. Advantages of the model approach over conventional analyses are discussed.