While stating that the South-West monsoon rainfall for the country as a whole is "most likely to be normal (96-104 per cent)", Kumar today said "the 'El Nino' effect (which can result in a deficient rainfall), will be known by the third week of June."
Quantitatively, the monsoon rainfall is likely to be 99 per cent of long period average with a model error of 5%, he added.
A statement circulated at Kumar's press conference here said, "The monsoon has set over Kerala and parts of coastal Karnataka and Tamil Nadu on June 5. The conditions are favourable for its further advance in the remaining parts of coastal Karnataka, Goa, South Konkan, South Maharashtra, interior Karnataka and some parts of Tamil Nadu and parts of North Eastern states."
"Recently, global models have given predictions based on May conditions. Some of the models have given predictions below average, while others have also predicted as normal and even above normal. It has been observed that skills of these models is yet to be proven as there is no consistency," he added.
"We are analysing conditions up to May for giving statistical forecast in third week of June, along with dynamical forecast," the statement said.