Southwest Monsoon made a timely arrival over the southern parts of the country however, it became quite slow wherein rains had seen enough reduction. There was quite a lot of rainfall variation in the month of June wherein the mid-week had seen positive rains after which activity reduced thereby increasing once again during the last week. With this, rainfall deficiency of June was at -5 percent.
As far as July is concerned, despite being a core Monsoon month, the first ten days were highly deficient with recovery being seen thereafter, however, rains once again reduced by the end and the month ended with a deficiency of -6 percent.
August, another core Monsoon month, remained a poor performer and there was no major recovery as such despite the flooding rains that had throttled the state of Kerala. Thus, the month of August ended with a deficiency of -8 percent.
Moving on to September, the month has also followed a similar track with the likely deficiency to be about -20 percent or more by the end, for September alone. This particular situation is not very common when all the four months under-perform. One or the other month ends up performing well relieving some burden from the previous month. Moreover, both July and August which are the core Monsoon months also known as compensatory months, support each other wherein one of the two months performs well.
The month has seen variations when the deficiency kept on rising. However, due to the rains occurring in view of Cyclone Daye the seasonal deficiency was at nearly -8 percent. However, due to absence of rains thereafter, the deficiency has now increased to -9 percent.
In the past, 1950 onward when all the four months have been deficient, invariably the seasonal deficiency was over 10 percent resulting in moderate to severe drought except 1985 where the country had recorded 93 percent of rains.
However, most of the years including 1951, 1965, 1972, 1987 and 2004 coincide with El Nino years which is linked with invariably overall failure of Monsoon. This year, the season has behaved differently which was a roll over of La Nina conditions. Devolving La Nina conditions do not usually spoil rains.
However, it quickly shifted towards warming of the oceans resulting in evolving El Nino conditions which could mature by the winter season this year.
This Monsoon season is expected to end at a deficiency of over 9 percent resulting in near drought conditions this time.
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