Collaborative Innovations in Coastal Flood Forecasting: NWS Eastern Region's Total Water Level Program and Partnerships with the Modeling Community

Five years ago, National Weather Service (NWS) Eastern Region coastal offices implemented and operationalized Total Water Level forecasts, with the aim of delivering actionable insights regarding projected coastal water levels. This initiative built upon three decades of model development, dedicated to delivering extratropical storm surge and water level guidance to the coastal forecast offices. NOAA's operational implementation timeline for these models included the introduction of the Extratropical Storm Surge Model (ETSS) in 1995, the Probabilistic Tropical Cyclone Storm Surge Model (P-Surge) in 2008, the Extratropical Surge and Tide Operational Forecast System (ESTOFS) in 2012, the Probabilistic Extratropical Storm Surge Model (P-ETSS) in 2017, and the National Water Model (NWM) in 2023.

Over the years, these models have evolved into the guidance familiar to forecasters today, conveying simulated water levels at in-situ stations, along coastlines, and overland locations. Aligned with the NWS’s mission to provide weather, water and climate data, forecasts, warnings, and impact-based decision support services for the protection of life and property and enhancement of the national economy, having robust tools and reliable model guidance is imperative. Currently, the NWS Eastern Region is the only region to provide daily water level time series forecasts for its designated coastlines. Utilizing tools developed by meteorologists in Eastern Region and continually refined through targeted development efforts encompassing forecast software and model output, the Total Water Level program stands as an undeniable success story. This success is underpinned by close collaboration with model developers and a collective focus on operational applications for the model guidance and associated technical improvements. Examples include the implementation of bias correction, improved data flow, the addition of new forecast point locations, enhancements to bathymetry and topography data, grid/mesh improvements, and other improvements. The modelers have consistently welcomed feedback from the field, and the program managers at the Eastern Region Headquarters have played a facilitating role in this feedback loop. This presentation will share examples of the collaborative activities that have been critical to the success of the Total Water Level project; and how the relationships and effective feedback efforts among the model developers, regional program managers, and operational forecasters have resulted in the development and implementation of model updates that have substantially benefited the NWS Eastern Region’s Total Water Level Program.