 Originating from an area of low pressure over the southern Bay of Bengal in early May 2013, Viyaru slowly consolidated into a depression on May 10.The depression gained forward momentum and attained gale-force winds on May 11 and was designated as Cyclonic Storm Viyaru, the first named storm of the season.Operationally, the system was referred to as "Mahasen"; however, this was altered in 2014 with the final report and all archived advisories changed to show Viyaru.