Though it NEM 2019 may not be active over Chennai & suburbs a lot of action is happening around the Indian Ocean. A combination of influence from planetary waves & favorable tropical conditions mean the Equatorial Indian Ocean on either side is teeming with activity. Add one of the strongest Positive IOD episodes in recent times to the mix you have got a potent concoction brewing.
The strong Positive IOD episode has meant Arabian Sea has pretty much shut down its big brother, Bay of Bengal, lock stock & barrel. Earlier this year we saw two simultaneous cyclones happening at the same time. Now we have two simultaneous Deep Depressions with one potential cyclonic storm on the way. 2019 has now set record for being the most active year over the Arabian Sea with 6 Depressions + Cyclones.
The satellite & wind charts of Indian Ocean pretty much shows how things are with multiple circulations all over the place. While most of these circulation are of academic interest as far as NEM is concerned the area of interest for us will have to be Comorin Sea & Equatorial Bay. Comorin Sea area is likely to see a possible LPA in a day or two which potentially could change the rainfall dynamics drastically for Tamil Nadu with a little bit more Northward movement compared to model estimates.
Similarly the trough of Easterlies over Equatorial Bay could potentially throw up another disturbance early next week under favorable MJO conditions. While today we could see major rainfall activity confined to South TN things are certainly pointing to a possible late season flourish by NEM 2019 under favorable support from MJO which is likely to influence the weather over Indian Sub Continent for the next week or so.