Twin Climate Systems May Reshape Indian Ocean Rainfall

The monsoon appears headed for another active phase, with a fresh low-pressure area forming over land on Friday and a second system set to develop over the Bay of Bengal by Saturday. The twin weather systems have prompted forecasters to reassess the broader atmospheric drivers behind the renewed revival. According to global climate models, the most likely trigger is an emerging positive Indian Ocean Dipole (IOD) being reinforced in turn by a rapidly strengthening El Niño over central and eastern tropical Pacific.

Though separated by thousands of kilometres, the two climate phenomena are increasingly interacting through atmospheric teleconnections, with the potential to reshape rainfall patterns across the Indian Ocean basin. Leading European model projects above-normal rainfall for Sri Lanka, Kerala, and Tamil Nadu (blue and green towards right) during October-December from an emerging positive Indian Ocean Dipole (IOD) phase. | Photo Credit: European Centre for Medium-Range Weather Forecasts.