Hydrometeorological Prediction Testbed Supporting the US National Water Model

Objective:

The overarching goal of this project is to design, implement and apply a community testbed (a real-world proving ground) for advancing hydrologic prediction science and practice. The testbed will facilitate the assessment and benchmarking of new techniques, models, model elements, workflows and datasets, and enable developers to refine and advance supporting components of prediction systems targeting distinct objectives (e.g., flash flood prediction, short to medium-range river flow prediction, sub-seasonal to seasonal water supply prediction) in a rational and evidence-driven manner. The major outcome of this effort will be establishing a system that enables methodical and evidence-driven comparison and adoption of new hydrologic prediction science (models, methods and datasets).

Abstract:

A key to the success of CIROH will be its ability to overcome the well-known research-to-
operations gap that has hampered the adoption of state-of-the-science modeling, methods and
datasets in pragmatic hydrologic prediction operations and applications. To this end, this
project will design and implement a ‘forecast testbed’ – a CIROH research activity centered on
hydrologic forecasting – to support the evaluation, selection and adoption of a variety of critical
forecasting capabilities for transition into the Nextgen framework supporting the National
Water Model. The testbed will create experimental protocols to rigorously assess and
benchmark new techniques, models, model elements, workflows and datasets, and enable
developers adding to the Nextgen system to refine and advance supporting components of
prediction systems targeting distinct objectives (e.g., flash flood prediction, or sub-seasonal to
seasonal water supply prediction) from an evidence-driven perspective. It will strongly
emphasize several main areas: the overall workflow for probabilistic or ensemble prediction,
strategies for developing and/or testing different model configurations, and assessing and/or
developing alternative probabilistic meteorological inputs (forcings and forecasts). At present,
there are few if any published benchmarks for US hydrologic forecast state-of-practice
performance or skill, which makes it difficult to determine, quantitatively, the extent to which
any new development in a forecasting system improves forecast skill. The testbed project will
begin to construct such benchmarks for US hydrologic forecasting performance or skill for a
priority set of forecasts: short-to-medium range river forecasts and S2S forecasts, including
water supply forecasting. Baseline capabilities for assessing performance will draw from current
working versions of NWS hydrologic forecasts for these products, including the current NWM
and Nextgen capabilities as well as River Forecast Center (RFC) capabilities. The major outcome
of this effort will be to establish a CIROH community testbed practice that promotes integrated
testing and benchmarking of new hydrologic prediction science (models, methods and data,
workflows) that can benefit national water modeling and prediction services.