Monsoon to cover all of India ahead of normal arrival time

NEW DELHI: The India Meteorological Department (IMD) has said that rainfall over the country for the month of July and August would be normal with a model error of 9 per cent at 96-104 per cent of the long period average (LPA). However, the development of a weak negative Indian Ocean Dipole ( IOD) during the second half of the monsoon (August onwards) could be a matter of concern.


"The monsoon will cover the entire country well ahead of the normal date for arrival. The northwest India will have rains a week ahead of the scheduled date," said LS Rathore, director general, IMD. He said that monsoon is likely to arrive over Delhi between June 18 and June 22 compared to the normal date of June 29. This year, the monsoon set over Kerala on June 1 compared to June 5 in 2012.

The July rainfall would be 101 per cent of the normal and August rains would be 96 per cent of the normal. The LPA of the season rainfall over the country as a whole for the period 1951-2000 is 89 cm.

Rathore said there was no direct relation between a weak IOD and monsoon as was with case of El Nino. The IOD, which affects the strength of the monsoon over the Indian subcontinent, is an irregular oscillation of sea-surface temperature in which the western Indian Ocean becomes alternatively warmer and colder that the eastern part of the ocean.

He, however, added that over the four broad geographical regions of the country, rainfall over the northwest India would be less compared to other parts of the country. Rainfall is likely to be 94 per cent of its LPA over the northwest India, 98 per cent of its LPA over central India, 103 per cent of its LPA over the south peninsular and 98 per cent of its LPA over the northeast with a model ±8 per cent. Current conditions were similar to the year 2008 when the monsoon had arrived on time.

According to DS Pai, director of long-range forecasting at IMD, the latest forecasts from over 30 model (dynamical and statistical) indicated that El Nino-Southern Oscillation (ENSO) neutral conditions are most likely (with a probability of about 65 per cent) to continue during the monsoon season. "The probability of the emergence of El Nino, which can reduce rainfall during the monsoon season, is very less," he said. ENSO is a band of anomalously warm ocean water temperatures that occasionally develops off the western coast of South America and can cause climatic changes across the Pacific Ocean.

The early onset of the monsoon should cheer farmers, as these are the most critical months for sowing. "The monsoon showers will have good bearing on the drought hit semi-arid corridor of India where we see timely sowing of coarse cereals," said Rathore.

He said that the rains would further help the raising of paddy nurseries and transplanting in fields across the country. For long-duration crops like cotton, sugarcane and plantation crops, the farmers' input cost would fall as use of irrigation facility would be negligible, he said.

In the first forecast issued in April 26, the southwest monsoon season rainfall for the country was slated to be 98 per cent of the with a model error of ±5 per cent. The cumulated seasonal rainfall over the country during the period June 1-13 was 128 per cent of LPA.