Kathmandu – A below-normal monsoon forecast for much of the Hindu Kush Himalaya (HKH) region may give a false sense of reduced flood risk, scientists have warned as rising temperatures and increasingly erratic rainfall patterns heighten the threat of flash floods, landslides and glacier-related disasters.
Recent cloudburst-triggered flooding in Pakistan’s Gilgit-Baltistan and intense rainfall-related flooding in Arunachal Pradesh, India, have highlighted a growing concern among climate experts: longer dry periods are increasingly being interrupted by short but extreme rainfall events that can overwhelm mountain communities.
The warning comes as the HKH Monsoon Outlook 2026 projects below-normal seasonal rainfall across much of the region.
“The biggest misunderstanding is that less seasonal rainfall means lower flood risk,” said Saswata Sanyal, Disaster Risk Reduction Specialist at the International Centre for Integrated Mountain Development (ICIMOD). “Seasonal forecasts describe average conditions over several months, not what happens in a single valley. Under El Niño, long dry spells can be interrupted by intense local storms that trigger devastating flash floods and landslides.”
Scientists say the changing pattern of rainfall is creating a more uneven and difficult-to-predict monsoon. While longer dry periods can increase stress on agriculture and water supplies, intense localised rainfall events can trigger sudden disasters within hours.
The risks are expected to increase further with above-normal temperatures across the region. Warmer conditions accelerate glacier and snowmelt in mountain areas, adding more water to rivers and increasing instability in glacier-fed river basins.
“The recent flooding in Pakistan’s Thore Valley demonstrates that hazards in the HKH are no longer occurring in isolation,” said Manish Shrestha, Hydrologist at ICIMOD. “Heavy rainfall, glacier melt, unstable slopes and fast-rising rivers can interact to create cascading disasters. Preparedness must reflect these compound risks rather than treating each hazard separately.”
The Hindu Kush Himalaya region, which stretches across Afghanistan, Bangladesh, Bhutan, China, India, Myanmar, Nepal and Pakistan, is highly vulnerable to climate-related hazards because of its fragile mountain terrain, glacier-fed rivers and growing human settlements.
Experts say governments need to prepare for multiple risks at the same time, including drought, heat stress, flash floods, landslides and glacier-related hazards.
Communities living along riverbanks, steep slopes and rapidly expanding urban areas remain particularly exposed, as infrastructure growth and settlements increase vulnerability in already fragile landscapes.
Neera Shrestha Pradhan, Water and Disaster Risk Reduction Lead at ICIMOD, said mountain communities will increasingly need to combine scientific forecasts with local knowledge as rainfall patterns become more unpredictable.
“Mountain communities have long combined scientific forecasts with local knowledge. That combination will become even more important as rainfall becomes more erratic,” she said.
Experts also stressed the need for stronger cross-border cooperation, as rivers originating in the Himalayas flow across national boundaries and hazards upstream can quickly affect communities downstream.
“Disasters across the HKH are becoming more frequent and increasingly complex, but preparedness systems are still largely designed around individual hazards,” said Qianggong Zhang, Head of Climate and Environmental Risks at ICIMOD. “Strengthening transboundary early warning and information sharing is becoming increasingly important for managing risks that cross river basins and national borders.”
With several weeks of monsoon activity still remaining, scientists say the key challenge is avoiding a narrow focus on rainfall totals alone.
A weaker monsoon season, they warn, can still bring dangerous floods if extreme rainfall events occur in vulnerable mountain areas.
