The equatorial sea surface temperatures continue to settle above average across the Pacific Ocean. However, the temperatures are on decline. In fact, the most recent Oceanic Nino Index (ONI) figure i.e. for NDJ (November-December-January) stands at 0.8°C as compared to 0.9°C in OND (October-November-December).
As reiterated, El Niño conditions are declared when the ONI which is three months running mean of SSTs anomaly in the Nino 3.4 region, is more than or equal to 0.5°C for overlapping 3 months for five consecutive episodes. The average value of ONI taken over a period of three months for the last five consecutive episodes are as follows:
Simultaneously, the weekly values for the SSTs are also witnessing weakening trend post December. Here’s a look at the recent Nino Index (in °C):
With all these factors, the El Niño probabilities which was 90% in December has now come down to 65% during the spring 2019. According to Skymet Weather, by the time Monsoon 2019 arrives the probability would be less than 50%. ENSO neutral conditions are on rise and thus, we can say 2019 would be a devolving El Niño.
Following image indicates the same wherein models are predicting decline in El Niño conditions.
With this, El Niño may not influence Southwest Monsoon 2019 up to a large extent. El Niño holds the power to rupture the Monsoon rains completely. During the devolving El Niño years, we can expect normal Monsoon rains or below normal rains, but above normal rains are ruled out.
Any information taken from here should be credited to skymetweather.com