The Stevens Flood Advisory System: Operational H3E Flood Forecasts for the Greater New York / New Jersey Metropolitan Region

The Stevens Flood Advisory System: Operational H3E Flood Forecasts for the Greater New York / New Jersey Metropolitan Region

N. Georgas A. Blumberg T. Herrington T. Wakeman F. Saleh D. Runnels A. Jordi K. Ying L. Yin V. Ramaswamy A. Yakubovskiy O. Lopez J. Mcnally J. Schulte Y. Wang 

Davidson Laboratory, Stevens Institute of Technology, USA

31 August 2016
| Citation



This paper presents the automation, website interface, and verification of the Stevens Flood Advisory System (SFAS, The fully-automated, ensemble-based flood advisory system dynamically integrates real-time observations and river and coastal flood models forced by an ensemble of meteorological models at various scales to produce and serve street scale flood forecasts over urban terrain. SFAS is applied to the Greater NY/NJ Metropolitan region, and is used routinely by multiple forecast offices and departments within the US National Weather Service (NWS), regional and municipal Offices of Emergency Management, as well as the general public. Every six hours, the underlying H3E (Hydrologic–Hydraulic–Hydrodynamic Ensemble) modelling framework, prepares, runs, data-assimilates, and integrates results from 375 dynamic model simulations to produce actionable, probabilistic ensemble forecasts of upland and coastal (storm surge) flooding conditions with an 81-h forecast horizon. Meteorological forcing to the H3E models is provided by 125 weather model ensemble members as well as deterministic weather models from major weather agencies (NCEP, ECMWF, CMC) and academia. The state-of-the-art SFAS, a replacement of the well-known, but deterministic, Storm Surge Warning System (SSWS) that was highlighted during Hurricanes Irene and Sandy and more recently extratropical cyclone Jonas, has been operational since the end of 2015.


early warning systems, emergency management, ensemble forecast, flood advisory system, integrated flood forecasts, river flooding, storm surge


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