El Nino likely to keep monsoon rains below normal, says Skymet

Private weather forecasting agency Skymet on Monday said the country is expected to see "below normal" monsoon rainfall this year, posing a potential risk for the crop output in the country.

It expects monsoon rains to be 94 per cent of the long period average (LPA) because of the impact of El Niño, which has reared its head after four consecutive years of normal to above normal rains. The LPA of rainfall is the precipitation recorded over a particular region for a given interval (like month or season), averaged over a long period (30 years, 50 years, etc).

In terms of quantum, the agency said that rains in the June-September period which provides more than 70 per cent of the country’s annual precipitation is expected to be 816.5 millimetres (mm) against the usual 868.8 mm.

The forecast is with an error margin of +/- 5 per cent. Despite possible risks to the economy, the performance of the agriculture sector also depends on timeliness, spread, and distribution of the monsoon rains.

State-run weather forecasting agency India Meteorological Department (IMD) will release its first forecast for the 2023 monsoon season later this month.

“The weak spot in the overall economy story has been agriculture, and any shock in terms of poor monsoon will definitely impact kharif production. It would be a major risk going forward, something which could keep inflation on the higher side even though the Reserve Bank of India (RBI) expects inflation to moderate in this fiscal year,” said Madan Sabnavis, chief economist at Bank of Baroda.

Skymet in its forecast also said it expects northern and central parts of the country to be at risk of rain deficiency. It further said Gujarat, Madhya Pradesh, and Maharashtra will receive deficient rains during the main monsoon months of July and August.

Punjab, Haryana, Rajasthan and Uttar Pradesh may also receive below normal rains in the second half of the season.

“Courtesy the triple-dip-La Niña, the southwest monsoon recorded normal/above-normal rainfall for the past four consecutive seasons. Now,  La Niña has ended. Major oceanic and atmospheric neutrals are in line with ENSO (El Niño-Southern Oscillation).  El Niño is more likely to become a major feature during the monsoon. The return of El Niño may predict a weak monsoon,” said Jatin Singh, managing director, Skymet.

The statement added that apart from  El Niño, there are other factors that affect the monsoon. The Indian Ocean Dipole (IOD) has the potential to moderate the monsoon and negate the ill effects of El Niño  if it is strong enough.

The IOD is now neutral and is trending towards being moderately positive at the onset of monsoon.

“El Niño and the IOD are likely to be 'out of phase' and there can be extreme variability in the monthly rainfall distribution. The second half of the season is expected to be more unusual,” Skymet said.

In terms of probability, the forecast said that there is a 40 per cent chance of monsoon being below average (90-95 per cent of the LPA), while there is a 25 per cent chance of it being even less than 90 per cent of the LPA. The LPA for southwest monsoon is 86.88 centimetres.

There is only 25 per cent chance of rains being average -- at 96-104 per cent of the LPA, according to the forecast, and 15 per cent chance of it being above average at 105-110 per cent of the LPA.

Month-wise, the forecast said that rainfall in June is expected to be at 99 per cent of the LPA (for June, it is 165.3 mm), while it will be 95 per cent of the LPA in July (for July, it is 280.5 mm).

In August, monsoon rains are expected to be 92 per cent of the LPA (254.9 mm), and in September, they are likely to be 90 per cent of the LPA (167.9 mm).