Extreme flooding in Arizona during the winter of 1993 resulted from a nearly optimal combination of flood-enhancing factors involving hydroclimatology, hydrometeorology and physiography. The flooding which occurred throughout January and February resulted from record precipitation due to a high frequency of winter frontal passages. These fronts were steered across the state by an exceptionally active storm track, located unusually far south. The number of individual storms that entered the region and the relative position of each storm track in relation to previous storms was reflected in a complex spatial and temporal distribution of flood peaks. An analysis of the hydroclimatic context of these floods supports a general conclusion that in Arizona, front-generated winter precipitation is the cause of the most extreme floods in large watersheds, even in basins that tend to experience their greatest frequency of flooding from other types of storms. A comparison of the 1993 floods with gaged, historical, and paleoflood data from Arizona indicates that although many individual flood peaks were quite large, they were within the range of documented extreme flooding over the past 1000+ years.