The gist of the Southwest Monsoon 2009 by IMD:

Southwest monsoon set in over some parts of south Bay of Bengal, Andaman & Nicobar Islands and entire Andaman Sea on 20th May.

Southwest Monsoon further advanced into some parts of south Arabian Sea, some more parts of south Bay of Bengal and some parts of eastcentral Bay of Bengal on 22nd May.

It further advanced into some more parts of south Arabian Sea, southern parts of Kerala & Tamil Nadu, most parts of southwest & eastcentral Bay of Bengal and some parts of westcentral & northeast Bay of Bengal on 23rd May. The normal date of onset of monsoon over Kerala is 1st June.

It advanced into remaining parts of south Arabian Sea, some parts of central Arabian Sea, remaining parts of Kerala, Tamil Nadu & Puducherry, most parts of westcentral Bay of Bengal, West Bengal & Sikkim, entire northeastern states and some parts of north coastal Orissa on 25th May.

Southwest monsoon has further advanced into some more parts of central Arabian Sea, coastal and south interior Karnataka, some parts of Rayalaseema and south coastal Andhra Pradesh and some more parts of west central Bay of Bengal as on 1st June.

The northern limit of monsoon passes through Lat. 14.0 °N/ Long. 60.0° E, Lat. 14.0 °N/ Long. 70.0° E, Udupi, Anantpur, Ongole, Lat. 17.0 °N Long. 85.0° E, Paradeep, Bankura and Gangtok as on 1st June.