Southwest Monsoon arrived in Kerala on Tuesday, three days ahead of schedule, said India Meteorological Department (IMD).
The onset of monsoon over the southern state marks the commencement of the four-month-long rainy season in the country.
June 1 is the official onset date for arrival of monsoon in the country and it takes more than a month-and-half to cover the entire country.
The IMD has made a forecast of “normal” rainfall this season.
“Today, the southwest monsoon has further advanced into remaining parts of southeast Arabian Sea, Comorin – Maldives area, entire Lakshadweep, most parts of Kerala, some parts of Tamil Nadu and some more parts of southwest, central and northeast Bay of Bengal”, said IMD statement.
Widespread rainfall occurred over Kerala, during the past 3-4 days. The 14 rainfall monitoring stations for Monsoon onset over Kerala have reported more than 60% rainfall from 25th May, added IMD’s statement.
According to the IMD, if after May 10, 60 per cent of the available 14 stations –Minicoy, Amini, Thiruvananthapuram, Punalur, Kollam, Allapuzha, Kottayam, Kochi, Thrissur, Kozhikode, Thalassery, Kannur, Kudulu and Mangalore — report 2.5 mm or more rainfall for two consecutive days, the onset of monsoon over Kerala can be declared on the second day. This is one of the main parameters for declaring the arrival of monsoon.
Besides this factor, the westerly winds must be up to 15,000 feet above main sea level and outgoing long-wave radiation less than 200 wm-2 (watt per square metre) to declare the arrival of monsoon.
In its forecast for next 48 hours, IMD said that conditions are favorable for further advance of southwest Monsoon into some parts of central Arabian Sea, remaining parts of Kerala, some parts of coastal and south interior Karnataka, some more parts of east central and northeast Bay of Bengal, and some parts of northeastern states during next 48 hours.
As per Skymet (private weather agency), ever since its arrival over Andaman and Nicobar Islands on May 25, the Monsoon has been progressing at a steady pace due to the twin weather systems prevailing on either side of the Indian coast which have been responsible for pushing the Monsoon surge over the region.
All the necessary parameters were met following which the onset of monsoon over Kerala was announced, Mritunjay Mohapatra, Additional Director General, IMD, said.
Since Monday, thirty people have died after thunderstorm accompanied by lightning lashed at parts of Uttar Pradesh, Bihar and Jharkhand.