Indian Ocean Dipole has finally come out from the bounds of the -ve threshold after a stint of over 5 months. However, La Nina shows no signs of softening and remains pervasive over the central and eastern Pacific.
ENSO: During the last 4 weeks, equatorial Sea Surface Temperatures (SSTs) remained below average across most of the Pacific Ocean. Over Nino 3.4 region, the principal measure of La Nina, the Oceanic Nino Index (ONI) remains <= 1deg.
ENSO probabilities for Nov 2022 predict SSTs to remain below normal at the level of La Nina till Jan-Mar 2023. Accordingly, La Nina advisory remains in place for November 2022.
IOD: Indian Ocean Dipole index for the week ending 06Nov 2022 was -0.33deg celsius. This was the first time after a stint of over 5 months, that the IOD broke the threshold barrier of +/-0.4 deg. to stay in neutral bounds. The latest value for the week ending 13Nov 2022 was -0.11 deg. and again a neutral mark. A trail of neutral values, week after week, will be a requirement to consider the ongoing -ve IOD event 'over'.
MJO: Potentially, a strong Madden Julian Oscillation event is emerging, albeit far from the Indian Ocean, an area of interest for Indian Seas. MJO with fairly large amplitude is sailing over the maritime continent and propagating eastward further away, over the Western Pacific. Such conditions become favourable for developing tropical cyclone over the Eastern Hemisphere. Bay of Bengal and the Arabian Sea are unlikely to host a cyclonic storm during the next 2 weeks.
La Nina conditions are not favourably linked with Northeast Monsoon rainfall. An excess of 12% rainfall over the South Peninsula till 31st Oct 2022 has now been reduced to a mere 6%. State of Kerala remains a deficit with a shortfall of 20% and Rayalaseema and Coastal Andhra Pradesh have also consumed their surplus rainfall of October 2022. Partial recovery of the Northeast Monsoon is likely during the next week.
