Monsoon reaches Kerala ahead of schedule

The south-west monsoon set in over Kerala today, heralding the four-month rainy season (June to September) about four days ahead of the normal schedule of June 1.

According to the Indian Meteorological Department (IMD), the conditions are favourable for advancement of the monsoon to some parts of the coastal and south-interior Karnataka and Tamil Nadu in the next two days.

The monsoon system has already covered the entire south-Arabian sea, and part of south-east Bay of Bengal. Its northern limit passes through Kannur, Palakkad and Kanyakumari.

Most parts of Kerala has been experiencing persistent rainfall with some heavy spells in the last couple of days.

The rain-bearing system strengthened further today with the deepening of flow over the Arabian sea and south peninsula. Besides, an off-shore trough has also developed, extending from Karnataka to Kerala coast, confirming the onset of the monsoon.

The IMD had earlier predicted the arrival of the monsoon in Kerala on May 24 but had subsequently withdrawn its forecast, citing changes in weather systems. Today, it formally declared the onset of the monsoon.

More rains are forecast in the entire region in the coming few days.

The long-range monsoon forecast, issued by the IMD on April 19, had projected the total rainfall till the September-end this year to be around 95 per cent of the long-period average rainfall in the country as a whole with a model error of plus or minus 5 per cent.

The IMD is expected to fine-tune this prediction, taking more factors into account, by the end of this month when it also issues the forecast for the rainfall in the agriculturally crucial month of July and for the country's four contiguous geographical regions "� north-west India, north-east India, central India and the southern peninsula.

Last year, the IMD had predicted 92 per cent of the normal rainfall but the actual rainfall during the entire season turned out to be 100 per cent of the normal.

This year, it has changed its monsoon prediction model in favour of two models that predict rainfall on the basis of 5 and 6 atmospheric parameters.