In Africa, more than 90% of harvests come from small-scale farmers and rely most on seasonal rainfall variability. A failure in the start of the rainy season can lead to loss of crops and reseeding, resulting in additional costs for farmers. An effective communication of climate information during the onset is crucial to avoid losses and support decision-making, particularly to the last miles. For example, knowledge of an early or late start to the rainy season would allow farmers to make strategic choices regarding the seed’s varieties, labor investments, and agricultural inputs. Accurate and accessible rainfall information enables farmers to decide not only when to plant and to harvest, but also when to dry the crops and to look out for the outbreak of pests and diseases that can ruin yields. To help farmers monitor the start of the agricultural season, ACMAD has developed an interactive tool that uses observed rainfall data to forecast the start of the season. This cutting-edge tool aims to respond to the needs of agriculture stakeholders in predicting and monitoring the season onset. As part of the implementation of the Global Framework for Climate Services in Africa through the Climate Services and Related Applications programme (ClimSA), the African Centre of Meteorological Applications for Development (ACMAD) in collaboration.