With about 45 days left of active Southwest Monsoon 2016 season (possibly 15 days of Peak Monsoon) left it is time to look at how this year’s Southwest Monsoon has evolved over South India over the last 75 days or so. As many will remember the Southwest Monsoon onset this year was slightly delayed over Kerala. Though the onset was delayed the early part of June saw pre monsoon conditions prevail over most parts of Peninsular India providing for some early momentum to the Southwest Monsoon season. Since then it has been pretty much downhill with Kerala seeing one of its worst monsoons in recent times.
While on the face of it if one looks at the chart as per IMD classification South Peninsular India is still seeing a normal monsoon with -4% variance over long term average. Dig a little deeper the numbers start looking scary. The chart progression clearly shows how following a good June has skewed the numbers so far with July & August looking bad. In particular the performance of the first fortnight of August has been very bad for South India.
If one takes this analysis a little further doing a bit of district tabulation the numbers show up the plight of Southwest Monsoon 2016 since June. As of 30th June 91 out of the 101 districts in South India had seen normal rainfall with 54 of those districts recording excess rainfall. In about 45 days time the tables have changed around with the 11 deficit districts increasing to 25 by 13th August.
While Kerala, Karnataka & Tamil Nadu have seen an increase in number of deficit districts during this period the case of Kerala is noteworthy with the table changing completely opposite. From 13 normal and 1 deficit district (Wayanad) now it 11 deficit districts in the state and crucially even the 3 normal districts are negatively normal effectively meaning all districts of Kerala as on date has recorded less than normal rains this Southwest Monsoon 2016.
A district wise progression chart for the three months indicate how things are progressively becoming worse for South India. For the month of August as on date only 8 out of the 101 districts recording normal rainfall in South India. If we thought things cannot become any worse the model outputs indicate weak monsoon conditions to prevail for most part of remaining August.
While its not doomsday yet as far as Kerala goes but its time the state kick starts a drought management program with only about 45 days of active monsoon left.