Increasing the value of weather-related warnings

Despite advances in forecasting and emergency preparedness, weather related disasters continue to cost many lives, to displace populations and to cause wide-spread damage. Therefore, High Impact Weather Project (HIWeather), a 10-year research project (https://public.wmo.int/en/resources/buHetin/hiweather-10-yearresearch- project), was established in 2016 by WM0 (World Meteorology Organization) WWRP (World Weather Research Program: https://www.wmo.int/pages/prog/arep/wwrp/new/wwrp_new_en. html). HIWeather aimed at achieving dramatic improvements in the effectiveness of weather-related hazard warnings, following recent advancement in numerical weather prediction at km-scale and in disaster risk reduction. The implementation plan was developed under the concept of warning chain, which comprises all components and the connections between to a successful weather-hazards warning: observations, weather forecast, hazard forecast, impact forecast, the generation of warnings and decision making (Fig. 1). A successful warning relies on information produced by the meteorological and related physical sciences, thus its effectiveness of delivery depends on applications of social, behavioral and economic sciences. The workshop of WM0 High Impact Weather Project was held in Beijing during 20-22 November of 2018, attracted a diverse and interdisciplinary group of over 70 scientists from 25 countries in the broad field of physical and social science, during which all elements of the warning chain were discussed critically.