The onset of south west monsoon over Kerala may be slightly delayed even as eastern India is about to receive another spell of heatwave in the next five days, India Meteorological Department said on Friday.
While the monsoon’s normal onset date is June 1, this time the met agency predicted that the monsoon might reach the Malabar coast three days later - on June 4. But scientists inside and outside IMD are now of the opinion that there may be a little delay even for the June 4 schedule.
"The onset over Kerala will happen between June 5-7 (both inclusive)," Akshay Deoras, research scientist at the National Centre for Atmospheric Science & Department of Meteorology, University of Reading told DH. Three specific weather phenomena, according to him, caused the delay.
“While tropical cyclone Mocha helped in a timely onset of the monsoon over southern parts of Andaman and Nicobar islands, there was a weakening of monsoon winds after it disintegrated. Tropical cyclone Fabien in the southern Indian Ocean added to this weakening by pulling and disorganising monsoon winds,” he said.
Absence of another travelling climate parameter known as the Madden-Julian Oscillation over the Indian Ocean didn't promote strengthening of monsoon winds in the second fortnight of May, Deoras said, explaining the reasons behind the onset delay.
“The onset can take place between June 4 and June 8,” commented D S Pai, a senior IMD scientist. The monsoon, according to the IMD, is set to advance into areas of the south Arabian Sea, Maldives, Comorin, south Bay of Bengal, east central Bay of Bengal, and parts of the northeast Bay of Bengal within the next 48 hours.
In the last five years the maximum delay in monsoon arrival was seen in 2019 when the monsoon reached Kerala on June 8 as against the forecast of June 6.
But since the IMD’s predicted arrival date has a margin of four days on either side, the official forecast remains accurate. That may very well be the case in 2023 too.
Meanwhile, the met department predicted a heat-wave like condition in eastern India affecting Bihar, West Bengal and Sikkim. The temperature will rise in the northwest that enjoyed a cool May whereas hot and uncomfortable weather is likely in Chhattisgarh and Andhra Pradesh because of increased heat and humidity.