Above-Normal Monsoon Rainfall Forecast for South Asia in 2025: A Boost and a Challenge for the Region

The 2025 southwest monsoon season, spanning from June to September, is projected to bring above-normal rainfall across most parts of South Asia, according to the South Asian Climate Outlook Forum (SASCOF). This forecast, developed collaboratively by the National Meteorological and Hydrological Services (NMHSs) of nine countries—Afghanistan, Bangladesh, Bhutan, India, Maldives, Myanmar, Nepal, Pakistan, and Sri Lanka—provides crucial insight for governments, planners, farmers, and disaster management authorities.

While the forecast promises increased water availability that is essential for agriculture and hydropower, it also raises concerns about the risks of flooding, landslides, and associated casualties. Notably, some parts of northern, eastern, and north-eastern South Asia may experience below-normal rainfall, highlighting the region's climatic diversity.

The Importance of Monsoon in South Asia

The Southwest Monsoon is a critical climatic phenomenon for South Asia, delivering 75–90% of the region’s annual rainfall in most areas except Sri Lanka and southeastern India. The rain it brings is the primary source of water for agriculture, hydropower, and drinking water, replenishing rivers, lakes, and underground aquifers.

For countries like India, Pakistan, Nepal, and Bangladesh, the monsoon season is the backbone of agricultural production, significantly impacting food security and the broader economy. It influences the planting and harvesting of staple crops like rice, maize, and millet. Hence, even slight variations in rainfall can have ripple effects across economic and social systems, including commodity prices and rural livelihoods.

2025 Forecast: Above-Normal Rainfall and Climate Conditions

The SASCOF precipitation outlook for June to September 2025 indicates that most areas in South Asia are likely to receive higher-than-average rainfall. However, localized regions in the north, east, and northeast are expected to have below-normal rainfall.

The forecast results from an expert consensus based on observed and projected global and regional climate drivers. Notably:

• ENSO (El Niño Southern Oscillation): Current conditions are neutral, with no strong El Niño or La Niña events expected through the monsoon season.

• Indian Ocean Dipole (IOD): Another key climate influencer for the monsoon, which will continue to be monitored closely for shifts that could affect rainfall distribution.

• Snow Cover Extent: The Northern Hemisphere’s winter and spring snow cover has a documented inverse relationship with South Asian summer rainfall. The January and March 2025 snow cover were the 4th and 6th lowest, respectively, over the last 59 years, suggesting a potential uptick in rainfall.

Economic, Agricultural, and Risk Management Implications

A forecast of abundant rainfall brings mixed implications. On one hand, it bodes well for:

• Agricultural productivity, especially in rain-fed farming systems.

• Hydropower generation, which is vital for countries like Nepal and Bhutan.

• Water resource management, as reservoirs and aquifers are replenished.

On the other hand, above-normal rainfall increases the risk of flash floods, river flooding, and waterborne diseases, particularly in densely populated and low-lying areas such as Bangladesh, parts of eastern India, and Pakistan’s Indus Basin.

To mitigate these risks, early warning systems, urban drainage upgrades, and disaster preparedness plans are essential. The “Early Warnings for All” initiative, championed by the World Meteorological Organization (WMO), plays a crucial role in strengthening resilience across the region.

SASCOF and Regional Cooperation

Founded in 2010 under the aegis of the WMO, the South Asian Climate Outlook Forum serves as a model for regional collaboration in seasonal climate forecasting. By pooling resources and expertise from NMHSs, SASCOF helps:

• Improve the accuracy of forecasts through shared data and models.

• Facilitate downscaling of regional predictions to local levels.

• Enhance preparedness in climate-sensitive sectors like health, disaster management, energy, and food systems.

These collaborative efforts are part of a broader network of Regional Climate Outlook Forums supported globally by WMO, underscoring its 75-year legacy of promoting transnational knowledge-sharing and climate resilience.

Hope with Caution

As the 2025 monsoon season approaches, South Asia must prepare to harness the benefits of abundant rainfall while safeguarding against its potential hazards. The forecast offers an opportunity to enhance agricultural output and water security, but it also demands heightened vigilance from policy-makers, emergency services, and communities.

Advance warnings and climate outlooks, such as those from SASCOF, exemplify how scientific forecasting can support sustainable development, protect lives, and drive economic resilience across one of the world’s most populous and climate-sensitive regions.