NOAA's COMMUNITY HYDROLOGIC PREDICTION SYSTEM

NOAA’s National Weather Service (NWS) is responsible for the production of the nation’s river flood forecasts and warnings in support of the protection of life and property and enhancement of national commerce. For the past thirty years, NWS hydrologists have used the NWS River Forecast System (NWSRFS) as the core infrastructure for their hydrologic operations. NWSRFS is remarkable in that it has met most of the NWS needs for such a long time. With increasing operational needs and escalating support costs, the NWSRFS will be retired and replaced by the Community Hydrologic Prediction System (CHPS). CHPS has been developed by the NWS in collaboration with Deltares (formerly Delft Hydraulics) in the Netherlands. The Delft-Flood Early Warning System (FEWS) serves as the infrastructure for CHPS with NWS hydrologic models and United States Army Corps of Engineers (USACE) hydraulic models providing the forecasting core. The CHPS migration project realizes significant improvements for the NWS and its hydrologic forecast offices. First, CHPS provides all of the “standard” benefits of a legacy system replacement – lower support costs, better use of modern computing technology, and increased fle xibility for adding service improvements. Second, the plug-and-play nature of CHPS expands our ability to partner with Federal, state, local and university researchers. Third, CHPS allows the NWS to re-examine its hydrologic forecast concept-of-operations, and consider new ways to meet its mission requirements. A fourth benefit is the immediate connection between the NWS and the international flood forecasting community through the Delft-FEWS user community. The NWS anticipates being able to exchange forecast techniques with many others very easily. The paper and oral presentation will delve more deeply into the topics mentioned above, including a more comprehensive description of the CHPS infrastructure, a comparison of pros and cons of CHPS versus NWSRFS, the CHPS migration project, anticipated benefits and lessons learned.