Accelerating Subseasonal-to-Seasonal Modeling and Improving Week-3–4 Forecasts with the Unified Forecast System: Plan and Progress

Accelerating Subseasonal-to-Seasonal Modeling and Improving Week 3-4 Forecast with Unified Forecast System: Plan and Progress

Yan Xue1, Dorothy Koch1, Vijay Tallapragada2, David DeWitt3, Tom Hamill4, James L. Kinter5, Cristiana Stan5, Lucas Harris6, Jessie Carman7

Subseasonal-to-seasonal (S2S) prediction supports important decisions in sectors ranging from food security and public health to water resource management and disaster risk mitigation. The National Weather Service (NWS) is accelerating S2S modeling as part of the NOAA’s Unified Forecast System (UFS), consisting of six component models of the Earth system: the FV3 dynamical core for the atmosphere, MOM6 for the ocean, Noah MP for the land surface, GOCART for aerosols, CICE5/CICE6 for sea ice and WW3 for ocean surface waves. The UFS is being built as a community model on software infrastructure components including the NOAA Environmental Modeling System (NEMS), the National Unified Operational Prediction Capability (NUOPC), the Common Community Physics Package (CCPP), the Joint Effort for Data Assimilation Integration (JEDI) framework, a unified workflow, and the Model Evaluation Toolkit (MET-plus) for verification and validation. The community can contribute to the development of the end-to-end S2S prediction system including coupled data assimilation, ensemble design, advanced physics, process-based diagnostic tools and S2S metrics, understanding of sources of predictability, and development of forecast products for the user needs. To accelerate this research to operation process, the UFS Steering Committee is initiating an “Application Team” that will develop and test the coupled UFS, providing a framework for community modeling to support extended-range forecasting. The NWS is building a strong collaboration with the NOAA Office of Weather and Air Quality (OWAQ) to accelerate the transition from research to operations. In this presentation, we will discuss the major challenges in S2S prediction that project onto NWS requirements for week 3-4 forecast products, and NWS plans and progress in the development of the coupled prediction system for weeks 3-4 forecasts.

1 Office of Science and Technology Integration/NWS/NOAA, Silver Spring, MD

2 Environmental Modeling Center/NWS/NOAA, College Park, MD

3 Climate Prediction Center/NWS/NOAA, College Park, MD

4 Earth System Research Laboratory/OAR/NOAA, Boulder, CO

5 Center for Ocean-Land-Atmosphere Studies/George Mason University, Fairfax, VA

6 Geophysical Fluid Dynamics Laboratory/OAR/NOAA, Princeton, NJ

7 Office of Weather and Air Quality/OAR/NOAA, Silver Spring, MD