The India Met Department has said that conditions are becoming favourable for a normal onset of South-West monsoon over south Andaman Sea and south-east Bay of Bengal by Saturday.
It did not elaborate further but satellite maps revealed that the south-westerly wind flows may pick up speed over the next couple of days around a building trough of lower pressure in the central Bay.
Trough in bay
By Tuesday, the trough of lower pressure will have concentrated into a low-pressure area as south-westerly wind flows gather even more steam, precipitating the onset of monsoon over the Andaman region.
The group of islands in south-east Bay of Bengal are the first stop for the monsoon in the Indian territorial waters.
The Arabian Sea arm of the monsoon normally reaches Kerala with a gap of 10 to 12 days hence.
On Wednesday, forecast assessment made by US National Centres of Environmental Prediction suggested that the low-pressure area in the Bay may further intensify into a depression in due course.
It could intensify even further and lead to onset of the Arabian Sea arm of the monsoon over the Kerala coast ahead of the normal date of June 1, this forecast said.
But the Met Department graphics suggest that this could be early days just yet, and may be overestimating the buzz in the Bay.
Arabian sea arm
Instead, it sees the possibility of an ill-timed circulation developing in the central Arabian Sea half-way to the Kerala coast by Wednesday.
The presence of an opposing and well-established circulation just to its North lends it to being vulnerably poised ‘right in the centre of nowhere.’
If it were to acquire some strength there, it is most likely that it will be spirited away to the northwest towards Oman-Yemen coast in the Persian Gulf as was the case with ‘rogue cyclones’ in the immediate past.
What it does to building south-westerly flows towards the Kerala coast is disrupt them and send them back scurrying to the East African coast to regroup and rebuild before charging in yet again.
Only redeeming factor is that they will have another week and a little more to do this, and still keep tryst with the Kerala coast.