It is the time of retreating monsoon. The skies are clearing, the tides are receding, the sea is less violent. It is the festival time for the people of the coastal areas. The people offer coconut to Lord Varun to invoke blessings and offer thanks giving.
For the fishermen is is the beginning of the new fishing season. During the monsoon the seas are more violent. The fishermen don't wade into seas during this time. Shravan Purnima signifies the end of Monsoon. The Fishermen decorate their boats, paint it new and put flags. They then carry decorated coconuts to the sea. It is kind of a community gathering there. They celebrate together, sing and dance together. In the end they worship the Sea God and offer coconut. The decorated coconuts are thrown in the water with prayers of a plentiful fish catch.
A coconut has three eyes. It is said to represent Lord Shiva, the three eyed God. Coconut is considered to be an auspicious offering to Gods. A coconut is broken in front of the deities before taking up a new venture to seek blessings and on successful comlition for thanks giving. Coconut is important for all religious occasions. Thus coconut is considered to be an ideal offering to the Sea God as well.
Pieces of coconut and coconut are distributed as 'prasad'. Coconut rice is the main dish on this day.