India received over 100% of its LPA 

  • The southwest monsoon this year has ended with an 8.7% surplus, surpassing estimates by the India Meteorological Department (IMD). 
  • This is also the first time since 2010 that India has got more than 100% of its long period average (LPA) of 88 cm in consecutive years. Last year, India saw record rainfall of 110% of the LPA, the highest in a quarter century.
  • India has never got over 105% of the LPA in consecutive years in at least 30 years, according to records available since 1988 on the IMD website.
  • These have been an unusually good couple of years for the monsoon.
  • The heavy rains this year have been due to several long-lasting low-pressure systems in the Bay of Bengal that fuelled heavy rain over large swathes of India in August. This wiped out the deficit in July, which is usually the rainiest of the four monsoon months. At 32 cm, August rainfall was nearly 26% more than what’s usual for the month.

Tad short of excess

  • A developing La Nina, the converse of an El Nino, which is a heating of the central equatorial Pacific and responsible for diminished monsoon rain over India, too, contributed to munificent rain this year. 
  • The IMD, in its forecasts, had anticipated ‘normal’ rain, defined as 96-104% of the LPA. Rains above 110% LPA are termed ‘excess’ and this year has fallen only a tad short. 
  • Of the 36 meteorological subdivisions that the IMD has partitioned the country into, 12 recorded ‘excess’ rain and 17 recorded ‘ normal’ rain. Only five divisions posted ‘deficient rain’.