Meanwhile, El Nino has strengthened from a “weak” to a “moderate” state and the latest update from US weather agencies late Thursday said there was a 66% chance of it developing into a “strong” event later this year. It said atmospheric conditions over the Pacific were now reflecting the El Nino state, which means its effects could henceforth be felt in other parts of the globe.
While rainfall across India since June 1 remains within the normal range of ±4%, the monsoon in August so far has been 29% below the long period average with south India having been particularly dry. Experts said the break in the monsoon, which began around August 5-6, was likely to continue till around August 16. While a couple of low-pressure systems thereafter were likely to bring rain in parts of east and central India, rainfall may remain largely subdued over the rest of the country till around August 24, as per IMD‘s forecast.
Meteorologist: Doesn’t look good for monsoon rainfall as August is set for a deficit
Although breaks in the monsoon such as the current one in the country following an active spell are not uncommon, what is likely to some concern is the projected prolonged period of the weak spell in the backdrop of what is now a full-blown El Nino that has the potential to impact rains during the rest of the monsoon season.
“It’s a classical break in the monsoon that we are seeing for close to a week now. It may last till around August 16, when a low-pressure system may form over the Bay of Bengal followed by another a few days later. These systems are likely to bring rain to states such as Bihar, Jharkhand and West Bengal in east India, and Odisha, Chhattisgarh, MP and some adjoining areas, as per IMD’s forecast. However, widespread rainfall across the country is unlikely till after August 20,” said M Rajeevan, veteran meteorologist and former secretary in the Union earth sciences ministry.
Based on the latest report of US agencies, Rajeevan said the El Nino was now a “coupled” system, meaning that the atmosphere over the Pacific, which had so far not fully responded to the warming in the ocean, had fallen in line with the El Nino. “The southern oscillation index (SOI) too has become negative, reflecting the El Nino state. These changes suggest that El Nino now has the potential to impact weather systems in other regions of the world,” he said.
“Overall, things do not look good for monsoon rainfall. August is set for a deficit. It is possible that the shortfall will be made up, at least in part, in September if a positive Indian Ocean Dipole (IOD) develops. But the government should start implementing a Plan B to contain the damage,” Rajeevan said.