Heavy precipitation events in small and medium-sized catchments can cause flash floods with very short lag times (a few hours) and high specific peak discharges. The rainfall and resulting rapid runoff can initiate geomorphic processes such as erosion, debris flows or shallow landslides, which mobilize large amounts of unconsolidated material and increase their destructive force.
Robust hazard assessments combined with early warning systems are essential to reduce the impacts of these events by enabling effective emergency management. This can be achieved by (i) increasing the forecast skill (improved predictions of physical variables or the hazard), or (ii) integrating additional information to support decision making.
Uncertainty sources in the forecasting chain include the high space-time variability of rainfall, limitations in observations and forecasts, the variability and nonlinearity of physical processes and their representation in models under extreme conditions, and incomplete exposure and vulnerability data to translate hazard forecasts into impacts.
This session presents recent advances in the monitoring, modeling and short-range forecasting of rainfall-induced hazards, the identification of hazard-prone areas, and the assessment of societal impacts with contributions on these themes:

- Development of new measurement techniques adapted to flash floods and hydro-geomorphic hazards (in-situ sensors and remote sensing data), and quantification of associated uncertainties.
- Short-range rainfall forecasting for heavy precipitation events, including seamless rainfall forecasting based on NWP models, nowcasts and/or ML, and ensemble-based uncertainty representation.
- Understanding and modeling of flash floods, hydro-geomorphic processes and their cascading effects, at appropriate space-time scales.
- Integrated hydrometeorological forecasting chains and new modeling approaches for flash floods and geomorphic hazards in gauged and ungauged basins.
- Observation, understanding and prediction of hazard, societal vulnerability and social responses to flash floods and/or hydro-geomorphic hazards.
- Development of impact-based approaches, integrating societal vulnerability.
- New approaches to validate hydrometeorological and impact forecasts, including new direct and indirect observation techniques.
- Assessment of possible evolutions in frequency and hazard characteristics due to climate change.
Contributions related to recent events are encouraged.