Since 2011, the coasts of North America, Mexico, and the Caribbean have experienced an unusual increase in the arrival of Sargassum. A large amount of Sargassum has caused significant economic losses in the tourism sector of the Dominican Republic as well as the entire Caribbean region. The present article discusses the possible factors contributing toward this unusual increase. Large Sargassum masses are generated in the Sargasso Sea. In this region, several current systems converge with the North Atlantic Subtropical Anticyclone (NASH), which has an area of displacement extending from Brazil to Africa. Sargassum is transported toward Africa, where it meets the Northern Equatorial Recirculation Region (NERR) before recirculating back toward the Caribbean in a clockwise pattern (Putman et al., 2018; Wang, 2007). Upon returning to the Caribbean and Gulf of Mexico, Sargasso grows flowers and distributes across the region. The effect of the North Atlantic Oscillation (NAO) is also analyzed as well as the possible influence of Sahara dust, which acts as a source of nutrients for the growth and development of Sargassum. In the Dominican Republic, the species found in the current study included Sargassum fluitans and Sargassum natans. As for the species Sargassum polyceratium var. ovatum, the variety ovatum has not been reported before on the coasts of the Dominican Republic. Key words: Sargassum arrival, Caribbean, Dominican Republic, Azore High.