 On January 10 , a tropical disturbance formed east @-@ northeast of St. Brandon , which is a small archipelago belonging to Mauritius . It originally consisted of a small , weak vortex , although it gradually organized . The system moved to the southwest and quickly intensified into a tropical depression , reaching peak winds of 50 km / h ( 30 mph ) . Despite it only being a depression , the Mauritius Meteorological Service named the depression Dona due to the threat to the island . The system turned more to the south ahead of a trough , passing east of St. Brandon and later to the west of Rodrigues . Later , Dona turned to the southeast , dissipating on January 14 without affecting land . 
