The proposed work will continue to maintain and further develop the existing implementation of the wwrp/wcrp sub-seasonal to seasonal prediction project (S2S) database and tools in the IRI data…

The proposed work will continue to maintain and further develop the existing implementation of the wwrp/wcrp sub-seasonal to seasonal prediction project (S2S) database and tools in the IRI data library (iridl), for a two-year period (20252026). The european centre for medium range weather forecasts (ecmwf) has committed to maintaining the S2S database after the formal completion of the S2S project in december 2023 for five years, until december 2028. This project will maintain and keep the S2S database up-to-date in iridl, including new model versions from the contributing forecast providers. IT will implement recent and planned developments for near real-time access to the forecasts from some models, greatly augmented ensembles from the ecmwf model (100 members issued every day), and add foreseen new U.S. Models from NASA and ncar. These new developments will make the S2S database much more useful in real time for climate services applications both in the U.S., as well as in the global south, than the previous implementation that was limited by a 3-week forecast delay behind real time. Beyond an S2S database copy in the U.S., iridl will continue to provide important tools and resources compared to those available through the other project archiving centers located in europe and china, accelerating S2S research and development of S2S applications across all sectors, particularly in the united states. These include pre-computed lead-time dependent model climatologies, server-side operations and opendap access that minimize data downloads and provide large labor savings for users these are significant advantage especially in bandwidth-limited environments and for S2S capacity-building workshops. In addition, having the S2S database archived at the same place as the U.S. Based subc and nmme databases at IRI is a big advantage for researchers, enabling a direct comparison of the american models with S2S models. The proposed work addresses noaas 2ND long-term mission goal weather-ready nation, where society is prepared for and responds to weather-related events. The S2S timescale between 2 weeks and a season, bridging the GAP between existing weather forecasts and seasonal climate outlooks is recognized to be a critical one for early warning of weather hazards and one in which significant advances are expected due to recent advances in models and MJO prediction skill in particular. Serving the S2S database in iridl will significantly contribute to achieving this goal by facilitating access by a broad spectrum of researchers and applications-developers, eliminating the need for users to laboriously download there own dark copy of the database and write their own analysis codes. The increased uptake will translate into development of improved S2S forecast products and user-applications, and will pave the way for applications of cloud computing to multimodel forecast datasets in the future