India has so far received 7% excess rainfall, monsoon likely to continue: IMD
New Delhi, September 7, 2020
India as a whole has so far received 7% excess rainfall and the monsoon is likely to continue with more rain predicted from the third week of September, the India Meteorological Department (IMD) said today.
M Mohapatra, Director General of the IMD, said the country was likely to see normal to above normal rainfall in September, though in the second week of the month, monsoon rain was likely to be deficient in most parts of the country, including the northwest and central India. But it was likely to resume after September 17, he added. The usual date for the monsoon to begin withdrawing is September 17.
M Rajeevan, Secretary, Earth Sciences, addressing a virtual press conference along with Mohapatra, said, “The plentiful and spread of southwest monsoon this year should help farmers and the output must be very good. It will also help the Indian economy, though exact quantification cannot be made at this moment. We don’t have an assessment as to how it will impact the economy.”
Mohapatra pointed out that the IMD in its weekly weather update mentioned that withdrawal of monsoon may begin from western parts of Rajasthan in the week ending September 18. “But we are also expecting a low-pressure area to develop over the west-central Bay of Bengal around that time. While the withdrawal of monsoon may begin, we are still studying as to when it is likely to completely withdraw.
“We are expecting normal to above normal rain in Kerala, Karnataka and coastal areas of Maharashtra around and after September 17,” he added.
In other words, though the rainfall activity has declined in September as compared to August and was now below normal, rains will revive in the next few days as fresh weather systems were developing, he said.
Mohapatra said the variability of monsoon rain this season was higher this year, with excess rain in June, a deficit in July and again excessive rainfall in August. An active Madden–Julian oscillation (MJO), the largest element of the intraseasonal (30- to 90-day) variability in the tropical atmosphere and cold El Nino neutral conditions also favoured good rain in August.
He noted that the IMD’s accuracy in forecasting heavy rainfall has improved to over 80 %. The IMD has accurately predicted the behaviour of Super Cyclone Amphan well in advance and helped save human lives and property.
However, the East and West coast cyclones were different weather patterns and tracking them minutely sometimes differ from the forecast. Though the cyclone Nisarga was also well tracked and predicted from a low-pressure area to its peak, there was some difference about its landfall.
Mohapatra pointed out that among some new initiatives by the IMD was its “Weekly video weather forecast” (in English and Hindi) and weather apps—Mausam App, Meghdoot App and Damini App, which were very useful for the people.
On the impact of climate change on the behaviour of Indian monsoon, Rajeevan said that it does have its effect and the IMD has done a lot of work on it. But these impacts vary from time to time and there was no uniformity about it, he said.
He also gave details about IMD’s efforts in the installation of more radars across the country to gather data and be able to make forecasts on various weather phenomena in the near future.