15th May 2020, New Delhi: The Southwest monsoon is slightly delayed and is likely to hit Kerala on 5th June with a model error of ± 4 days predicts IMD.
Southwest monsoon sets over Kerala on 1st June with a standard deviation of about 7 days. However in the last 5 years, monsoon arrival has seen an average delay of about a week in 2015, 2016 & 2019.
Advance of the southwest monsoon over Indian main land is marked by monsoon onset over Kerala and is an important indicator characterising the transition from hot and dry season to a rainy season.
Once arrived in Kerala, it also covers parts of its adjacent states like Tamil Nadu and Rayalaseema and also some parts from north- eastern states like Tripura, Nagaland, Manipur and Mizoram.
As per the new normal, the monsoon sets over Kerala around 1st June, nearly same as the existing normal date. However, monsoon withdrawal from northwest India is delayed by more than 2 weeks compared to the existing normal date of withdrawal (i.e. 1st September).
Monsoon retreats from most parts of the country except south Peninsula and some parts of neighbouring central India by 15th October coinciding with the existing normal and subsequently northeast monsoon gets established over south Peninsula