The India Meteorological Department (IMD) on Monday forecast the onset of the southwest monsoon over Kerala around May 26, nearly a week ahead of its normal arrival date of June 1, while issuing heavy rainfall alerts across several districts in the state.
According to the IMD, the monsoon onset date may vary by four days on either side of May 26. The weather office also said heavy rain accompanied by lightning and strong winds is likely in parts of Kerala and Mahe over the next five days.
The department attributed the weather conditions to a cyclonic circulation over south coastal Andhra Pradesh and adjoining areas, which is expected to lead to the formation of a low-pressure area over Kerala, south interior Karnataka, Rayalaseema and the southeast Arabian Sea adjoining south Lakshadweep.
The IMD said the southwest monsoon has already advanced into most parts of the southeast Arabian Sea and parts of the Kanyakumari region. It has also progressed into most parts of the southwest and southeast Bay of Bengal, most of the Andaman Sea, the Andaman and Nicobar Islands and parts of the east-central Bay of Bengal.
Earlier, the IMD had said, "All the criteria are satisfied for the advance of southwest monsoon over the region."
The weather agency also noted that conditions remain favourable for the monsoon to advance further into more parts of the southeast Arabian Sea, southwest and southeast Bay of Bengal during the next three to four days. The remaining parts of the Andaman Islands and Andaman Sea, along with some areas of the east-central Bay of Bengal, are also likely to witness the onset during this period.
Amid intensified rainfall activity, the IMD issued an 'orange alert' for Kannur and Kasaragod districts in Kerala on Monday, while a 'yellow alert' was sounded in 10 districts, excluding Thrissur and Palakkad. For Tuesday, a yellow alert has been issued for nine districts.
An 'orange alert' indicates very heavy rainfall of 11 cm to 20 cm, while a 'yellow alert' indicates heavy rainfall between 6 cm and 11 cm.
Kerala’s monsoon onset marks the beginning of the four-month southwest monsoon season from June to September, which is crucial for India’s agriculture sector and water reserves.
"On average, the southwest monsoon takes about 10 days to enter South Bengal from Kerala," Regional Meteorological Centre (RMC) Kolkata head H.R. Biswas said.
The IMD had earlier stated that India may witness below-normal rainfall during this year’s monsoon season due to the possible emergence of El Nino conditions, which are generally associated with reduced rainfall over the country.
