Nepal is acutely vulnerable to drought. Around 60 percent of the Nepalese households are engaged in agriculture (National Statistics Office, 2022), and the agricultural sector supports the livelihoods of roughly two-thirds of the total population (FAO, 2023). Economic losses in farm and off-farm sectors over the last five years alone have amounted to NRs. 415 billions, excluding infrastructure damage due to climate change (National Statistics Office, 2022). Drought risk is growing, particularly during the pre-monsoon and winter seasons, when declining rainfall combines with rising temperatures and increased agricultural water demand. Winter droughts are becoming more frequent, especially in the western Terai, where a persistent downward trend in precipitation has been documented since mid-1990s (IFRC, 2025), threatening food security and livelihoods for rain-fed farming communities. Trend analyses across multiple stations and time scales indicate that both the severity and frequency of drought events are increasing across Nepal (Dhital et al., 2015, Sharma et al., 2021, Bhandari et al., 2021, Dahal et al., 2015).

Despite this vulnerability, Nepal currently lacks a high-resolution, continuously gridded drought monitoring system grounded in physically based model. Earth observation based tools do exist for Nepal, most notably the ICIMOD National Agricultural Drought Watch developed under the SERVIR-HKH Initiative and the broader Regional Drought Monitoring and Outlook System for the Hindu Kush Himalaya (ICIMOD, 2024b). These systems provide valuable district-level aggregated drought indicators based on remote sensing indices. However, they do not provide the spatially continuous, process-based soil moisture characterization at high resolution that is possible with a fully distributed hydrological model. The Nepal Drought Monitor (NDM) addresses this specific gap by applying hydrological modelling approach from proven operational systems such as the German Drought Monitor and the emerging European Drought Monitor directly to Nepal's terrain and hydro-climatic conditions.

Nepal Drought Monitor (NDM) takes inspiration from the scientific foundation of the German Drought Monitor (GDM), which is also the precursor of the European Drought Monitor (EDM). Like EDM, NDM's workflow closely follows that of the GDM, while the operational control for EDM and NDM are based on the ecFlow - the workflow manager from ECMWF. In fact, the NDM is based on the git fork of EDM's ecFlow suite and the updates between the two are synced continuously. Like GDM, the NDM aims to demonstrate the value of hydrological-model-based drought indicators and position itself as a useful tool for near-real-time drought characterization and communication to the public and policymakers in Nepal.