Forecast with a model error of 4 days: Monsoon likely to arrive in Kerala early this year

Pune: The southwest monsoon is likely to set over Kerala on May 27, five days earlier than normal, the India Meteorological Department (IMD) said on Saturday.The southwest monsoon, which brings 70% of India’s annual rainfall, is crucial for the agriculture sector that contributes about 20% to the gross value added in the country’s economy and supports around half of its 1.4 billion population. Its timely arrival and distribution are also key as most of the kharif sowing takes place during the first two months of the four-month rainy season.

The weather office had on April 15 predicted that the 2025 monsoon rainfall would be above normal at 105% of the long-period average, which currently is 87 cm for India.

The forecast has a model error of four days, suggesting that the actual onset could occur four days earlier or later, the IMD said in a statement.

The June-September southwest monsoon usually sets in over Kerala on June 1, with a standard deviation of about seven days. Last year, it made landfall on May 30.

As the monsoon progresses northward, it provides relief from scorching summer temperatures. It usually covers the entire mainland by early July 8.The IMD has been issuing forecasts from 2005 for the date of monsoon onset over Kerala. According to it, during the past 20 years (2005-2024) the operational forecasts of the date of monsoon arrival over Kerala were proved to be correct, except in 2015.