Met department forecasts above normal monsoon for 2016
Two-thirds of the country's 1.3 billion people depend on the farm sector for their livelihood.
It said conditions are becoming favourable for the onset of monsoon and it would hit the Indian coast in the next 4-5 days.
Region wise, the seasonal rainfall is likely to be 108% of long period average (LPA) over northwest, 113% over central and southern India, and 94% over eastern India, said LS Rathore, director general at IMD.
The monthly rainfall over the country as a whole is likely to be 107% of LPA during July and 104% in August, both with a model error of plus/minus 9%.
Rathore said initially, the rainfall in June will be less, but it will pick up in the latter part of the month.
"There has been some progress of the monsoon. It is becoming strong in the Bay of Bengal and in a few more days it will strengthen in the Arabian Sea," said DS Pai, head of long-range weather forecasting at IMD.
Various factors from cyclone Roanu, higher temperatures over the Indian Ocean and the weakening of El Nino has led to the transition from pre-monsoon to monsoon onset over the Kerala coast.
From May 18 till date, the monsoon has remained static over the Bay of Bengal, giving good rains to Myanmar. It should have covered Sri Lanka and entered India by May 25.
On May 15, the weather office had said that the southwest monsoon is likely to set over Kerala on June 7, with a model error of plus or minus four days. Last year, the monsoon arrived six days late on June 5.
In April, the weather office had said rains during the four-month monsoon this year will be 6% higher than the long-period average. It said there is a 94% chance that the monsoon will be normal or surplus, with a 30% probability of excess rainfall. The weather office forecast of a surplus, well-distributed monsoon rains this year after two consecutive droughts cheered farmers and kindled hopes of a surge in rural demand on a good harvest.
Last year, monsoon rain was 14% below normal, while in 2014 there was a 12% deficit.
The IMD treats June 1 as the normal date for the arrival of the monsoon over the southern coast, based on rainfall data of over 100 years.