Many water management sectors are already having to cope with extreme weather events, climate variability and change. For this purpose, climate services provide science-based and user-specific information on possible impacts. Such information can be based on weather forecasts or on climate projections. In this context, predictions on sub-seasonal, seasonal to decadal timescales are an emerging and essential part of hydrological forecasting. With horizons ranging from months to a decade, these probabilistic forecasts are used in industries such as transport, energy, agriculture, forestry, health, insurance, tourism and infrastructure.

This session aims to cover the advances in climate and hydrological forecasting, and their implications on forecasting extreme events and servicing water users. It welcomes, without being restricted to, presentations on:

- Making use of climate data for hydrological modelling (downscaling, bias correction, temporal disaggregation, spatial interpolation and other technical challenges),
- Methods to improve forecasting of hydrological extremes,
- Improved representations of hydrological extremes in a future climate,
- Seamless forecasting, including downscaling and statistical post- and pre-processing,
- Propagation of climate model uncertainty to hydrological models and impact assessment,
- Lessons learnt from forecasting and managing present day extreme conditions,
- Effective methods to link stakeholder interests and scientific expertise,
- Operational climatic forecasting systems.

The session will bring together research scientists and operational managers in the fields of hydrology, meteorology and climate with the aim of sharing experiences and initiating discussions on this emerging topic. We encourage presentations from initiatives such as the H2020 IMPREX, BINGO, S2S4E and CLARA projects, and from WWRP/WCRP S2S projects that utilise the recently established S2S project database, and all hydrological relevant applications.