Monsoon onset over Kerala is likely to take place by June 3, the Indian Meteorological Department (IMD) said on May 30, while updating its prediction factoring in the latest meteorological indications. IMD had on May 14 predicted it to be around May 31 with model error of +/- 4 days. The normal onset date of the southwest monsoon falls on June 1 with a standard deviation of seven days. Though the private weather forecasting agency, Skymet Weather, claimed arrival of monsoon over Kerala on May 30 itself terming it a “slightly mild” onset, the IMD preferred to stick to all the defined parameters/criteria for onset of monsoon over the state. Citing an example, he said the rainfall over Kerala decreased along with weakening of westerly winds on May 30. IMD has been issuing operational forecasts for the date of monsoon onset over Kerala from 2005 onwards. It claimed that the operational forecasts of the date of monsoon onset over the state during the past 16 years (2005-2020) were proved to be correct except in 2015. Watch the video to know more.