OHD/HL/HSMB - Hydraulics: Wind

Define NWS Requirements for Adding
Wind Modeling Capabilities into HEC-RAS

Local wind and weather patterns or the passage of fronts can affect water levels in rivers, lakes, ocean inlets, and ocean shores. Wind effects are particularly important in coastal areas. Strong offshore winds can move water away from coastlines while onshore winds may act to pile up water onto the shoreline or push water through the coastal rivers. Prolonged wind can cause elevated water levels in the direction of prevailing wind. Recognizing the need for wind modeling, RFCs within the NWS have identified modeling wind as a critical functionality for the RFC’s daily forecast operations (Hydraulic Model Evaluation Team, 2007). The Hydraulic Model Evaluation Team report recommends immediate inclusion of wind modeling capabilities into the Hydrologic Engineering Center-River Analysis System (HEC-RAS) model.

Currently, work is underway to include the HEC-RAS model in the suite of NWS hydraulic models. HEC-RAS v. 4.0 does not have a wind modeling capability but we plan to work with HEC to get this capability added. From this study, we will produce a document recommending methods to the Hydrologic Engineering Center (HEC) to add wind forcing into HEC-RAS according to the RFC modeling requirements and published scientific guidelines. The study will evaluate existing wind modeling and parameterization schemes, and also consider the spatial and temporal resolution of available observed and forecast wind data.