High-impact hydro-meteorological events produce the most destructive and costly outcomes of any weather-driven phenomena world-wide. Furthermore, despite significant progress over the last several decades, forecasting and warning for these events still lacks the precision that could minimize loss of property and life, especially in developing nations. However, new observational platforms (in-situ, remote) and data-collection methods are improving our ability to assess ongoing events as well as forecast and distinguish those that could be destructive from those that probably will not be. Excessive precipitation or runoff associated with tropical cyclones/convection, land-based convection, atmospheric rivers, ENSO, wintertime snow-melt, rain-on-snow, etc. results in both flash-flooding and large-river system floods whose characteristics often depend on local soils, vegetation/agriculture, and topography. Conversely, severe droughts create deleterious impacts on crop/food production and the water supply. In this session, papers are invited that contribute to our ability to improve real-time/operational forecasts and warnings for these kinds of extremes, especially observational (as well as modeling) approaches that may vary depending upon differing societal contexts. In addition, papers that address promising and innovative methods of assessing and modeling the statistics of observed hydro-meteorological extremes as applied to real-time/operational forecasting/warning systems are encouraged. Papers that document forecast system performance vis-a-vis the effect of including new or additional observations are also encouraged. Please contact the session chair, Ana Barros (firstname.lastname@example.org) or the session organizer, John McHenry (email@example.com) for additional information.