The intensification of the El Nino atmospheric pattern in the equatorial Pacific Ocean poses a growing threat to the Indian southwest monsoon. Following temporary respite brought by rains during July and early August, the strengthening oceanic phenomenon is expected to depress rainfall levels across significant parts of the country. This shift in climatic conditions threatens to impact agricultural outputs and create water scarcity in vulnerable agricultural belts.
Drastic Reduction in Seasonal Rainfall Forecast
Updated rainfall projections released by private weather forecasting agency Skymet Weather indicate a sharp downturn for the overall southwest monsoon season. The agency now expects cumulative seasonal rainfall to reach only 85 percent of the long-period average. With half of August and the entire month of September remaining, the growing impact of El Nino has elevated the probability of drought conditions across the region to 70 percent.
This revised figure represents a significant drop from Skymet's initial forecast issued in April, which had projected four-month seasonal rainfall at 94 percent of the long-period average. However, shifting global oceanic and atmospheric indicators over recent weeks have necessitated a downward revision as El Nino strengthens faster than previously anticipated.
Projected Deficits for August and September
Monthly projections highlight further disruptions for the remainder of the monsoon. August rainfall is likely to end with a deficit of 16 percent below the long-period average. Conditions in September appear equally concerning, with rainfall expected to fall 20 percent short of normal levels. Weather analysts attribute this continued suppression of rainfall to the combined effect of a robust El Nino and a weak Indian Ocean Dipole.
Official Meteorological Projections and Field Data
The official India Meteorological Department had initially projected seasonal monsoon rainfall at 92 percent of the long-period average during its April assessment. In June, the department lowered this figure to 90 percent, citing a 60 percent probability of a deficient monsoon season. The department has not issued an updated full-season forecast since that June announcement.
Observed precipitation figures illustrate the extent of the current deficit. Between June 1 and August 17, the country received 518.7 mm of rainfall compared to the normal average of 596.2 mm for this timeframe. This represents a nationwide cumulative shortfall of 13 percent. The deficit in August has hovered consistently between 11 percent and 13 percent. By comparison, the rainfall shortfall stood at 40 percent at the end of June before recovery during July brought it down to 13 percent. Although flooding has been reported in localized river catchments, large swathes of agricultural land remain exposed to moisture stress as monsoon activity slackens in the latter half of August.
Oceanic Conditions Driving the El Nino Event
Explaining the atmospheric mechanics behind the phenomenon, Jatin Singh, Managing Director of Skymet Weather, stated that strong coupling between oceanic and atmospheric currents in the equatorial Pacific Ocean is accelerating the development of El Nino. He noted that this weather pattern could transition from a strong to a very strong category by early September, further worsening rainfall deficits across India.
