<!– /11440465/Dna_Article_Middle_300x250_BTF –>This year, the country will see normal southwest monsoon rainfall, the India Meteorological Department (IMD) said in its first long-range monsoon forecast on Tuesday.”The monsoon seasonal rainfall is likely to be 96 per cent of the long period average with a model error of 5 per cent on either side. This will be good for agriculture,” said KJ Ramesh, Director General, IMD.As per historical data of the past 50 years, the long-period average (LPA) rainfall – between June and September – is 89cm. The IMD categorises rainfall in the 96 per cent to 104 per cent LPA range as normal while the rain immediately below that, it is considered below normal.Even as the IMD has predicted a normal monsoon, uncertainties still loom in the form of an El Niño, that is likely to gain strength from August onward. The IMD has predicted that there is an increasing probability, of more than 50 per cent of El Niño conditions developing over Equatorial Pacific after August.El Niño is an abnormal condition over Equatorial Pacific Ocean, with warming over central and east Pacific Ocean. The warming results in below-par rainfall across the subcontinent and South Asia.The other uncertainty lies in the dynamical mode of forecasting. In a major departure, the IMD has given primacy to this model over the ensemble statistical model that has been in use since 2007. The dynamical model, also known as the Coupled Forecast System, collates data on local as well as global weather patterns to simulate a forecast for a specific duration. Due to the use of this model, the IMD has not issued specifics on the probability of an above normal and excess rainfall. It also did not reveal spatial distribution of monsoon across the regions.IMD DG Ramesh said that the this time, both, statistical prediction model and dynamic model assessments were identical. The IMD’s forecast has also relied heavily on predicting the gauging the impact of El Niño and the Indian Ocean Dipole (IOD). “There is possible development of El Niño over the Pacific and simultaneously we are seeing possibility of positive IOD. Because of this particular blessed situation will see good distribution of monsoon rainfall,” said Ramesh.The forecast of a normal monsoon will enthuse the farming sector as last year’s good monsoon has led to record production of oilseeds, food grains and also triggered a 4.2 per cent agriculture growth.

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Monsoon to be normal this year: IMD