The 2023 South-West monsoon has exited the country on Thursday leaving the ground clear for the North-East monsoon to settle over parts of the South Peninsula. India Meteorological Department (IMD) said the winter monsoon may commence over the next three days, but its initial phase would likely be weak despite a depression alert over the Bay of Bengal, too. 

The Arabian Sea is already under a depression alert, with a preparatory low-pressure area awaiting intensification over the South-West Arabian Sea, away from Lakshadweep and the West Coast of India. The counterpart ‘low’ over the Bay is expected to form by Saturday and intensify as a depression by Monday, closer to the Andhra Pradesh coast. 

Twin systems but...

In normal circumstances, twin systems over the Arabian Sea and the Bay are the perfect recipe for sustained rain over land. Not likely this time, since they are oriented otherwise and going away to be of meaningful consequence for the North-East monsoon. The north-easterly winds are projected to remain weak until the end of the month, as per IMD’s short-term guidance. 

No major mark-up in rainfall is indicated over the South Peninsula until next Tuesday next. The following couple of days might see scattered to fairly widespread light to moderate rain over parts of Kerala, Tamil Nadu, coastal Andhra Pradesh and Yanam. Elsewhere, Odisha and the North-Eastern States may benefit as the prospective depression likely heads in that direction. 

Above normal for Kerala

Global weather models continue to indicate possibility of normal rainfall for Kerala and parts of adjoining South Tamil Nadu through this period and extending into the first week of November. IMD too tends to agree in its short-term guidance. Updated outlook for November from a South Korean model raises this to above-normal rain for these regions but below normal for the rest of Tamil Nadu, entire Karnataka, Rayalaseema, Telangana and Coastal Andhra Pradesh. 

The South Korean model’s projections for December suggest rainfall trend may come back to being normal or above normal for not just the entire South Peninsula but also over the country at large, with excess rain indicated for North-West India. This trend is likely to hold for another month during January as the New Year dawns, though it will begin to fade over the South in February. March and April are likely to stay dry for the South Peninsula but wet over the rest of the country, according to this model.