India set for above-average monsoon with 105% of normal rainfall, predicts IMD

Indian Meteorological Department’s (IMD) Long Range Forecast for the seasonal rainfall predicted an above-average rainfall of 105% of LPA (long period average) with a model error of ± 5% for 2025.

“The forecast for the southwest monsoon season rainfall during 2025 was prepared based on the April initial conditions of a group of coupled climate models which have higher prediction skill over the Indian monsoon region,” said the statement from the Union Ministry of Earth Sciences.

It also noted that the LPA of the season rainfall over the country as a whole for the period 1971-2020 is 87 cm.

Since 2003, India Meteorological Department (IMD) has been issuing the operational long-range forecast (LRF) for the southwest monsoon seasonal (June-September) rainfall averaged over the country as a whole in two stages, as per the ministry.

“The first stage forecast is issued in April and the second stage or updated forecast is issued by the end of May. In 2021, IMD has implemented a new strategy for issuing monthly and seasonal operational forecasts for the southwest monsoon rainfall over the country by modifying the existing two stage forecasting strategy,” it said.

As per the new LRF strategy, the first stage forecast issued in middle of April consists of the quantitative and probabilistic forecasts for the country as a whole, and the spatial distribution of probabilistic forecasts for the tercile categories (above normal, normal, and below normal) of the seasonal (June-September) rainfall over the country.

The ministry informed that the “second stage forecast issued around end of May consist of update for the seasonal rainfall forecast issued in April along with the probabilistic forecasts for the seasonal rainfall over the four homogenous regions of India (northwest India, central India, south Peninsula and northeast India) and monsoon core zone (MCZ)”.

Quantitative and probabilistic forecasts for the country as a whole, and the spatial distribution of probabilistic forecasts for the tercile categories (above normal, normal, and below normal) of the June rainfall over the country are also issued during the second state forecast.

The forecast based on both dynamical and statistical models suggests that quantitatively, the monsoon seasonal rainfall is likely to be 105% of the Long Period.