Nearly half of India's farmland, without any irrigation cover, depends on annual June-September rains to grow a number of crops. Monsoon usually hit Kerala on the south coast around June 1 and covers the whole country by mid-July. Skymet, a private weather forecasting agency, had declared the arrival of monsoon in Kerala on Monday.
"The southwest monsoon has set in over the southern state of Kerala, three days ahead of its normal date," the Met Department said in a statement today.
The arrival of monsoon is declared by the state-run weather office IMD after several parameters measuring the consistency of the rainfall over a defined geography, intensity, cloudiness and wind speed are met.
As per the weather office, if 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 monsoon arrival.
Lasy month, MD Monsoon Director General K.J. Ramesh predicted the monsoon rains were expected to be 97 per cent of a long-term average.
India's weather office defines average, or normal, rainfall as between 96 per cent and 104 percent of a 50-year average of 89 cm for the entire four-month season beginning June.
(With inputs from PTI, Reuters)