The India Meteorological Department announced on 15 October that the southwest monsoon had withdrawn from the entire country. At the same time, northeast monsoon rainfall activity commenced over Tamil Nadu, Puducherry and Karaikal, coastal Andhra Pradesh, Rayalaseema, south interior Karnataka and Kerala-Mahe.
The transition is climatologically important because the northeast monsoon is a major rainfall season for southeastern peninsular India, especially Tamil Nadu. Withdrawal of the southwest monsoon is based on observed atmospheric and rainfall conditions; it is not simply a fixed calendar date.
For civil-services preparation, relate the event to seasonal wind reversal, the retreating monsoon, Bay of Bengal systems and the distinct rainfall climatology of southeastern India. A national southwest-monsoon withdrawal does not mean rainfall stops across India, because different seasonal and synoptic systems can become active.