In this work, we present a simple model that allows us to easily obtain the character of the dominant air mass for any location in the Northern Hemisphere at any time. Specifically, in this article the model has been tested at Valencia, Spain, for the years from 2006 to 2009. The classification of the air masses is performed analysing their trajectories over pre-defined source regions in the Northern Hemisphere. Daily trajectories were simulated by the hybrid single-particle Lagrangian integrated trajectory model (HYSPLIT) and then classified by our model. In order to verify our classification results, those cases identified as African were compared with the Saharan dust intrusions reported for Valencia by the Ministerio de Medio Ambiente y Medio Rural y Marino (MARM) in collaboration with the Centro Superior de Investigaciones Científicas (CSIC). The model we present in this article can be applied in the selection of an optimum aerosol model for the atmospheric correction of remote sensing products.