Date:22/03/2006 URL: http://www.thehindubusinessline.com/2006/03/22/stories/2006032201251900.htm

Back Normal monsoon likely

Vinson Kurian

45 pc probability that neutral conditions will prevail

La Nina conditions, normally considered supportive of a normal monsoon regime in India, continue to persist in the equatorial Pacific.

Thiruvananthapuram , March 21

The country is likely to have a normal monsoon during the upcoming season, going by the seasonal predictions of the International Research Institute (IRI) for Climate and Society, Columbia University.

India Meteorological Department (IMD) is expected to come out with its annual monsoon forecasts next month. The country had a normal monsoon the last season as well.

La Nina conditions, normally considered supportive of a normal monsoon regime in India, continue to persist in the equatorial Pacific. In its update, the IRI said that sea surface temperatures (SSTs) are approximately one degree C below average across much of the central-eastern equatorial Pacific.

With the persistence of below-average SSTs in the eastern equatorial Pacific, the maintenance of La Nina conditions remains the most likely outcome for the coming three-month (March-May) season.

However, there is some uncertainty surrounding the continuance of these cold SST anomalies. There is now an estimated 53 per cent likelihood for La Nina to persist and a near two per cent probability for the contra-indicated El Nino, leaving 45 per cent probability that neutral conditions will prevail over the period.

PRE-MONSOON RAIN

Meanwhile, pre-monsoon showers seem to be providing a taste of things to come, at least in some parts of the country.

The trend was most pronounced in the meteorological sub-division of Tamil Nadu and Pondicherry, where all except two districts recorded excess rain in the first 15 days of March.

The margin of deviation (in percentage figures) was of the order of +1000 Madurai; +757 in Virudhunagar; +642 in Dharmapuri; +582 in Krishnagiri; +557 in Sivaganga and +566 in Tuticorin.

The district of Chennai, including the city, recorded +384; only Theni (-81 per cent, scanty) and Cuddalore (-27 per cent, deficient) provided notable exceptions. And there is more to come. The National Centre for Medium Range Weather Forecasting (NCMRWF) has predicted that isolated rains and thundershower activity over peninsular India and the North-eastern States may continue over the next three to four days as well.

As for the North and Northwest, a fresh western disturbance is likely to approach Jammu and Kashmir and the adjoining hilly regions by Thursday.

Under its influence, the hilly regions and parts of adjoining plains of Northwest India are likely to receive isolated to scattered rains.