The Southwest Monsoon officially bid farewell to India on Thursday (October 19), marking its withdrawal four days later than the typical date of October 15, according to the India Meteorological Department (IMD). This year, it commenced its retreat from the Indian subcontinent on September 25, which was eight days after the normal date.

Typically, the Southwest Monsoon makes its grand entrance over Kerala by June 1, and by July 8, it usually blankets the entire nation. However, the withdrawal process usually begins around September 17, culminating with its full retreat by October 15.

"The Southwest Monsoon has withdrawn today, October 19, from the remaining parts of the country," the IMD said in a statement.

As the easterly and northeasterly winds establish themselves over southern peninsular India, IMD predict the onset of Northeast Monsoon rainfall in the region within the next three days. Nevertheless, it anticipates that the initial phase of the Northeast Monsoon will generally be weaker than usual.

During the four-month monsoon season from June to September, India recorded "below-average" cumulative rainfall, measuring 820 mm, compared to the long-period average (LPA) of 868.6 mm. This deviation from the norm was attributed to the strengthening El Niño conditions. The IMD, however, pointed out that positive factors such as the Indian Ocean Dipole (IOD) and the Madden-Julian Oscillation (MJO) partially alleviated the impact of El Niño, resulting in "near normal" precipitation levels.

In the four years leading up to 2023, India had recorded "normal" and "above-normal" rainfall during the monsoon season. Precipitation ranging from 96 percent to 104 percent of the long-period average is typically considered normal. El Niño conditions, characterised by the warming of Pacific Ocean waters near South America, are often linked to weaker monsoon winds and drier conditions in India.

The Indian Ocean Dipole, on the other hand, is defined by temperature differences in the western and eastern parts of the Indian Ocean, near Africa and Indonesia, respectively.

Additionally, the Madden-Julian Oscillation, a large-scale atmospheric disturbance originating in tropical Africa and travelling eastward, typically lasting 30 to 60 days, has a known influence on increasing convection in the Bay of Bengal and the Arabian Sea.

With inputs from PTI

(Edited by : Ajay Vaishnav)