The weekly Niño indexes are already indicating that El- Niño has reached threshold neutral. On May 23, the Niño 3.4 that is associated with the Southwest Monsoon declined to 0.2°C, which is a neutral value.
This is for the first time since January 2015 that Niño 3.4 values have fallen so much.
This figure has created a stir across the world, forcing international weather agencies to watch the demise of El- Niño even more closely now. The weather phenomenon that has been prevailing since last 14 months has severely impacted the weather across the world, particularly Indian Southwest Monsoon that resulted in 14% deficit in 2015.
However, formal demise of El- Niño can only be declared when the overlapping 3-month season average (Oceanic Niño Index) will settle below 0.5°C.
The latest Oceanic Niño Index for the months of February, March and April is still settling at a fairly high value of 1.6°C. “Looking at the present scenario, it seems that secession of El-Nino may take some more time though the indexes are declining continuously,” said AVM GP Sharma, President- Meteorology, Skymet Weather.
Skymet Weather predicts that final news of El- Niño being over will only come after the onset of Southwest Monsoon over the Indian mainland, sometime in June or July.
La Nina watch
El- Niño is usually followed by La-Niña, however, it is not essential every time. But this time weather conditions are indicating towards the arrival of the same.
Weathermen across the world have already issued La- Niña watch, as the temperatures over Pacific waters have been consistently showing a decreasing trend.
However, we do not foresee La Niña setting in before October. For the declaring the onset of La Niña, the Oceanic Niño Index needs to fulfill the criteria of settling below -0.5°C for five consecutive months.
Unlike El- Niño, La Niña is associated with good rainfall over the Indian region. Statistics suggests that La- Niña years have mostly resulted in above average rainfall.
Read: What is La-Nina?
Monsoon 2016 in India
We are at a stage where El- Niño is devolving, while La- Niña is evolving. Both the weather patterns will have their respective impact on the upcoming Southwest Monsoon.
On one hand, fading El- Niño will make way for neutral weather conditions after the onset of the Monsoon 2016. While on the other hand, an evolving La- Niña also has the great potential to affect the Monsoon in terms of good rainfall.
And as the weather models indicate, India is all set to witness above normal rainfall to the tune of 109% of the long period average (LPA) of 887 mm for the four-month period from June to September.
Please Note: Any information picked from here must be attributed to skymetweather.com