New Delhi: The India Meteorological Department (IMD) on Monday (September 7, 2020) predicted more rain from the third week of September across India, while the Ministry of Earth Sciences stated that the country as a whole has so far received 7 per cent excess rainfall.
M Mohapatra, Director General of the IMD, said that the country is likely to see normal to above normal rainfall in September, though, in the second week of September, monsoon rain is likely to be deficient in most parts of the country, including northwest and central India.
"But it is likely to resume after September 17," he said.
Notably, the monsoon usually begins to withdraw from September 17.
"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, " expressed M Rajeevan, Secretary, Ministry of Earth Sciences.
M 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. He said, adding that while the withdrawal of monsoon may begin, but we are still studying as to when it’s 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 said.
"Though the rainfall activity has declined in September as compared to August and is now below normal, rains will revive in the next few days as fresh weather systems are developing," he opined.
Mohapatra elaborated that 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.
He said 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 expressed that the IMD’s accuracy in forecasting heavy rainfall has improved to over 80 %.
Both Rajeevan and Mohapatra also pointed out that the IMD has very accurately predicted the behaviour of Super Cyclone Amphan well in advance and helped save human lives and property.
However, they admitted that East and West coast cyclones are 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 also include its "Weekly Video weather forecast" which is available in English and Hindi and weather apps like Mausam App, Meghdoot App and Damini App, which he said are very useful for 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 is no uniformity about it," he opined.
The Secretary, MoES also gave details about IMD’s efforts in the installation of new and more radars across the country to gather more data and be able to make forecasts on various weather phenomena in near future.
