The southwest monsoon arrived two days earlier than usual on Thursday hitting the Kerala coast and parts of Northeast India simultaneously. This early onset, driven by favourable conditions created by cyclone Remal, has pulled the monsoon flow to the Bay of Bengal, according to the scientists from the India Meteorological Department (IMD). This marks the beginning of the four-month rainy season in the country.
The typical monsoon onset date for Kerala is June 1, and for Arunachal Pradesh, Tripura, Nagaland, Meghalaya, Mizoram, Manipur, and Assam, it is June 5.
However, while Kerala and the Northeast regions have welcomed the monsoon rains, Delhi and several areas in Northwest and Central India continue to endure intense heat under the scorching sun with the IMD forecasting some respite in these regions soon.
"The Southwest monsoon has set in over Kerala and Mahe, and has advanced into most parts of Northeast India, including Nagaland, Manipur, Mizoram, Arunachal Pradesh, and most parts of Tripura, Meghalaya, and Assam as of May 30, 2024," said the IMD scientists. On May 15, the weather office had predicted the monsoon onset over Kerala by May 31.
Kerala has been experiencing heavy rainfall over the past few days, resulting in a surplus of May rainfall, with waterlogging reported from various parts, according to weather office data.
The IMD declares onset of monsoon over Kerala anytime after May 10 over 14 stations there and neighbouring areas receive 2.5 mm or more rainfall for two consecutive days, the Outgoing Longwave Radiation (OLR) is low, and the direction of the winds is southwesterly.
The IMD has warned of widespread rainfall till June 2 even as the National Human Rights Commission has asked Kochi corporation to address waterlogging within 8 weeks.
El Nino conditions are prevailing at present, and La Nina may set in by August-September, said the IMD scientists. El Nino - the periodic warming of surface waters in the central Pacific Ocean - is associated with weaker monsoon winds and drier conditions in India. La Nina - the antithesis of El Nino- leads to plentiful rainfall during the monsoon season, explained the scientists.
