India, May 27 -- The Mumbai monsoon arrived two weeks ahead of schedule on Monday, dropping more than 250mm of rainfall in South Mumbai and exposing the civic administration's utter lack of preparedness. While heavy rain was patchy in the suburbs, South Mumbai was hardest hit.

Several localities that never experience waterlogging in South Mumbai were flooded on Monday. The deluge began at midnight on Sunday and by 11am, areas such as Colaba, Breach Candy, Kemps Corner, Fort, Churchgate, Marine Drive, the high court area, Mantralaya, Grant Road and Nana Chowk were inundated - more than 250mm in just 13 hours.

According to the India Meteorological Department (IMD), rainfall over the 250mm mark is considered 'extreme'.

The chaos was inten...