Extreme weather, and especially heavy rain, has a major impact on urban populations and landscapes, and damages caused by urban flooding are increasing world-wide. Key challenges in reducing the impacts are to provide good quality detailed weather forecasts, to accurately measure high resolution space-time precipitation, to quantify flooding in urban drainage systems, evaluate flood risk and plan practical flood defense measures. Similar challenges apply to the effects of rain in natural landscapes, the triggering of landslides, debris flows, and other natural hazards. Climate change provides an additional uncertainty to deal with when analyzing potential impacts of heavy rainfall in the future.
UrbanRain Workshops are a regular series of international workshops on precipitation in urban areas which address these problems at the interface of science and practice. The workshops have taken place every 3 years since 1989 in the St Moritz area in southern Switzerland. They provide a focussed forum for exchanging new scientific ideas and advances in urban hydrological practice. Accordingly, contributions at the workshop address both scientific and operational aspects of rainfall impact analysis. The format of the workshop is informal with presentations, posters and adequate time for discussion and exchange.