Monsoon arrives early, and simultaneously in Kerala, northeast

NEW DELHI: Marking the beginning of the four-month rainy season in the country, IMD on Thursday announced the arrival of monsoon simultaneously over Kerala and most parts of northeast India including Nagaland, Manipur, Mizoram, Arunachal Pradesh and most parts of Tripura, Meghalaya and Assam.
While monsoon showers hit Kerala two days ahead of the normal date of onset on June 1, it has set in over northeast India six days before the normal date of June 5.

The monsoon's arrival over Kerala and northeast simultaneously is not very common. The last time it happened was seven years ago on May 30, 2017 triggered by Cyclone Mora that formed over Bay of Bengal. This time, Cyclone Remal was the trigger.
The monsoon covers the entire country by July 8. It normally arrives in Delhi-NCR in the last week of June.
As per IMD's forecast, monsoon rainfall during the June-Sept season is most likely to be 'above normal'.
The monsoon has also advanced into most parts of Lakshadweep area, most part of south Arabian sea and some parts of central Arabian sea and some parts of south Tamil Nadu.
In the last over 50 years (since 1971), the earliest monsoon onset over Kerala was recorded on May 18, 1990 followed by May 22, 1999 and May 23 in 1974 and 2009.
Though both Kerala and northeast India have been getting rains over the past few days, the Met department announced the arrival of Monsoon only after it met all the features associated with onset parameters on Thursday.
The Met department has been issuing operational forecasts for the date of Monsoon onset over Kerala from 2005 onwards. An indigenously developed state of the art statistical model with a model error of ± 4 days is used for the purpose. Referring to past 20 years data, IMD claimed that its operational forecasts of the date of Monsoon onset over Kerala were proved to be correct except in 2015.