India is expected to witness an active spell of the southwest monsoon over the next two weeks as oceanic and atmospheric conditions over the Indian Ocean and the Bay of Bengal become increasingly supportive of widespread rainfall. Weather experts cited by India Today say the favourable outlook comes even though the Indian Ocean Dipole (IOD), a climate pattern that can significantly influence the monsoon, remains in a neutral phase.
At present, the Indian Ocean has not developed the temperature pattern associated with a positive IOD. Per India Today, scientists say winds over the eastern tropical Indian Ocean are currently being influenced by tropical westerlies, recent typhoon activity in the western Pacific and the strengthening effects of El Nino. The characteristic southeasterly trade winds linked to a positive IOD have not yet emerged.
Indian Ocean remains active
Despite the neutral IOD, meteorologists say the atmosphere over the eastern Indian Ocean remains highly active, with persistent thunderstorm activity continuing across the region.
Experts note that because the Indian Ocean is relatively smaller than the Pacific, weather conditions can evolve quickly. If El Nino strengthens further in the coming weeks, it could encourage the formation of a positive IOD, which has often helped reduce some of El Nino's adverse influence on India's monsoon.
Another development being closely monitored is the gradual cooling of sea surface temperatures near Indonesia and the island of Java. This cooling is linked to seasonal upwelling, a process in which colder water from deeper ocean layers rises to the surface. Scientists say rainfall changes over Indonesia are closely tied to this phenomenon and can affect weather patterns across the wider Indo-Pacific region.
Bay of Bengal systems expected to boost rainfall
Meteorologists also point to improving atmospheric conditions over India. Short-lived rain-bearing systems have become more active over northern and eastern parts of the country, while the Madden-Julian Oscillation (MJO) is moving into a phase that favours cloud formation over the southern Bay of Bengal.
The combined effect of these weather systems is expected to support widespread monsoon activity across several regions over the next fortnight.
While the Indian Ocean Dipole has not yet shifted into a positive phase, scientists say evolving ocean temperatures and atmospheric patterns will remain under close watch, as they are likely to play an important role in shaping the progress of the remaining 2026 monsoon season.