Status and Plan in Developing and Implementing Medium-Range Weather, Subseasonal and Seasonal (S2S) Forecast Systems Based on the Unified Forecast System at NOAA

Warm Shade: Surface Temp, Contour: MSLP, Cool Shade: Convective Cloud Cover, Arrows: 10m Wind

The Unified Forecast System (UFS) is a community-based coupled Earth modeling system designed to support the Weather Enterprise and serve as the foundational infrastructure for NOAA’s operational weather prediction models. Under the UFS Research to Operations Project (UFS R2O), the Office of Science and Technology Integration (OSTI) Modeling Program in the National Weather Service (NWS) has collaborated and coordinated with the UFS community to develop a global coupled forecasting system consisting of six integrated Earth System component models: the FV3 dynamical core (atmosphere), MOM6 (ocean), Noah-MP (land surface), GOCART (aerosols), CICE6 (sea ice), and WW3 (ocean surface waves). This six-way coupled global UFS provides a basis for developing the next generation Global Forecast System (GFSv17) for deterministic medium-range forecasts up to 16 days, the Global Ensemble Forecast System (GEFSv13) for probabilistic subseasonal forecasts up to 48 days, and the Seasonal Forecast System (SFSv1) for probabilistic seasonal forecasts up to one year.

A SFS Development Plan has been drafted with a goal to build SFSv1 as a replacement for the more than one decade-old Climate Forecast System version 2 (CFSv2). To gather community feedback on the SFS Development Plan, better align modeling priorities with the needs and requirements of stakeholders/users for NOAA’s subseasonal and seasonal applications (GEFS and SFS), and also share best practices in developing S2S applications around the world, the OSTI Modeling Program hosted the first NOAA's Subseasonal and Seasonal Applications Workshop in September 2024. The workshop provided crucial feedback pertaining to the ongoing trajectory of the SFS development project and kickstarted a continuous dialogue among modelers, stakeholders/users, and researchers that will ensure that modeling priorities are aligned with the stakeholder needs and requirements and advancements in science and technology are continuously incorporated into the SFS development and implementation process.

At the AGU Town Hall, a panel of speakers will discuss recent progress and plans in the research and development of the three Global UFS Applications, including UFS infrastructure, testing and evaluations, dynamics and physics advancements, model component improvements, coupled data assimilation and initialization strategy, ensemble design, and process-level diagnostics of model errors. We seek community feedback on all of these aspects, particularly in the science and technology approaches, used in the development of the three UFS Applications. Questions, comments, and suggestions are greatly appreciated. We hope this town hall will serve as an avenue to hear community feedback and explore opportunities for collaboration and contribution from the community that help NOAA accelerate the development and implementation of the Global UFS Applications.

Desired outcomes of the town hall include:

• Providing updates in the development and implementation of GFSv17, GEFSv13 and SFSv1
• Articulating the advancements in science and technology incorporated and to be incorporated in GFSv17, GEFSv13 and SFSv1
• Discussing challenges, needs and gaps in research & development for the three Global UFS Applications
• Discussing avenues for collaboration and contribution from the community

A panel of speakers include:

• Vijay Tallapragada, NWS/NCEP/EMC: Global Forecast System (GFSv17, Physics, Land)
• Neil Barton,  NWS/NCEP/EMC: Global Ensemble Forecast System (GEFSv13)
• Phil Pegion, OAR/PSL: Seasonal Forecast System (SFSv1)
• Clara Draper, OAR/PSL: Coupled Data Assimilation and Initialization Strategy
• Jun Wang,  NWS/NCEP/EMC: UFS Infrastructure and Global Workflow