The Indian Meteorological Department (IMD) has issued the first stage of its operational long-range forecast for the south-west monsoon this year, with early predictions showing a likelihood that Garo Hills, West Khasi Hills and South West Khasi Hills will experience greater than average rainfall with the rest of the state facing a drier than average monsoon.
A second stage forecast will be released at the end of May, when the models and the data they predict should be more accurate.
Over the whole of India, the IMD predicts that the 2025 south-western monsoon will most likely be above normal, at 105 percent of the long period average (an average calculated from the figures from 1971 to 2020). The margin of error is ±5 percent.
“As sea surface temperature (SST) conditions over the Pacific and the Indian Oceans are known to have a strong influence on the Indian monsoon, IMD is carefully monitoring the evolution of sea surface conditions over these Ocean basins,” a release from the IMD stated today.
The release also noted the inverse connection between snow cover in the Northern Hemisphere and the strength of the Indian monsoon.
“The winter and spring snow cover extent over the Northern Hemisphere as well as Eurasia has in general an inverse relationship with the subsequent Indian summer monsoon rainfall. The areas of Northern Hemisphere snow cover and Eurasian snow cover during January to March 2025 were observed to be below normal,” it said, suggesting that India is in for a wetter than average monsoon.
The IMD data presented on a country map showed that most states have a high probability of a stronger than average monsoon. However, eastern Meghalaya, most of Assam, Tripura, Manipur and Mizoram are likely to be drier. Parts of Ladakh and nearly the whole of Tamil Nadu will also likely receive less rainfall than usual.
