Yesterday IMD officially announced the cessation of Northeast Monsoon over Peninsular India. In a way NEM 2024 ends up as another classic La Nina influenced monsoon. As with La Nina when the pendulum swings either way the season ended up as excess. Since 1950 out of the 25 years when Monsoon has withdrawn on or after 10th January La Nina influence was seen in 14 of them. Interestingly since 2000 monsoon withdrawal more often than not has pushed into 2nd week of January. This becomes critical in the context of bulk of Paddy harvest in TN happening around Pongal. In contrast the preceding 50 years saw only 9 years when monsoon withdraw beyond 10th January.
In a way NEM 2024 also highlights the challenges we need to be prepared. On the one hand we had instances like Cyclonic Storm Fengal giving unprecedented rains. On the other hand we also had longer dry spells in between these rainfall episodes. Abnormality is slowly becoming the new normal for Northeast Monsoon as well. The rains around Pongal festival this year meant some parts of Delta districts suffered losses at the time of harvest. Similarly longer drier spells also put more strain on the farming community from rain fed areas during monsoon time.
While NEM 2024 may have come to an end officially yesterday there could be rains over parts of TN in the next couple of days. Weather models indicate today and tomorrow to see relatively drier weather over most parts of the state. On Thursday light / moderate rains are expected to happen over parts South TN. Friday and Saturday more places in the state may see light / moderate rains. Ensembles indicate only parts of South TN which may see heavier spells of rains closer to the Ghats. The rest of the state is more likely to light / moderate rains at best.
In all probability places like Chennai in North TN may see drizzles / light rains during the night or early morning hours. But the overall expected rainfall quantum is expected to be less than 3 cms cumulatively for the next 7 days for most district headquarters in the state. South TN could possibly see a few places exceed more than 5 cms over the next few days. Places in the Manjolai ghats may see moderate to heavy rains around Thursday / Friday. With MJO expected to move further East from Maritime Continent slowly the gaps between rainfall events will increase. Also the intensity of each rainfall event will also be weaker than the previous event.
All in all NEM 2024 has officially checked out yesterday and is likely to wind down atmospherically by end of the week.
