Rainfall in August had been the least in over a century, with India getting 36% less rain than it usually does in the month. Of the four monsoon months, August usually sees the most amount of rainfall (25.4 cm) after July’s 28 cm.
With a strengthening of the El Nino and unfavourable conditions both in the Arabian Sea and the Bay of Bengal, August rainfall has been markedly deficient in most of India, except in northeastern India, the Himalayan States, and parts of Tamil Nadu, according to data from the India Meteorological Department (IMD).
El Nino refers to a warming of the central Pacific that usually translates to deficient monsoon rainfall over India.
The last time India recorded such severe deficits in August was in 2005, when the shortfall was about 25% of the normal, and in 2009, when India saw its biggest drought in half a century and August rainfall was 24% less than what was due.
Rainfall in August has brought the overall, national deficit to 10%, with the regional deficits being 17% in east and northeast India, 10% in central India, and 17% in southern India.
“There is an increasing trend in the break days,” M. Mohapatra, Director General, IMD, said. “Break days refer to rainless stretches during the monsoon months of June-September.”
The IMD on July 31 had indicated that August rainfall would be “below normal” but its weather models did not indicate that the shortfall would be as sharp as has been experienced.
Monsoon rainfall in September, the last of the four monsoon months, is likely to be within a 10% window of the 16.7 cm that’s usual for the month, the agency’s forecast noted.
“While there’s a reasonable chance of normal rainfall, thanks to favourable conditions in the Indian Ocean and two rain-bearing low pressure areas in the Bay of Bengal, getting extra rain is quite difficult,” an IMD meteorologist, who declined to be identified, said.