Unified Forecast System: Considerations for Transition to Operations

The Unified Forecast System (UFS) is, as stated on the community portal https://ufscommunity.org/, “a community-based, coupled, comprehensive Earth modeling system. The UFS numerical applications span local to global domains and predictive time scales from sub-hourly analyses to seasonal predictions. UFS is designed to support the Weather Enterprise and to be the source system for NOAA's operational numerical weather prediction applications”. NOAA’s National Weather Service is working with the broader community on the development of the UFS modeling framework based on publicly available codes, community infrastructure for components and system integration as well as community verification tools. This presentation will highlight two aspects that are important for transition of UFS codes to operations.

A test plan is critical for building and utilizing applications of a modeling framework and a fundamental document for the transition to operations process. The test plan spans from the initial stages of the development and evaluation of an improved parameterization, tool, method or a modeling component to their testing, evaluation and integration into an end-to-end system. If successful, this is followed by their operational implementation. Considerations for several characteristics of testing will be discussed including priorities, framework for an end-to-end system, hierarchy, community best practices and automation.

Improvement of the transition to operations process is an ongoing goal. Towards this goal the Environmental Modeling Center has collected feedback about the experience from the Global Forecast System (GFS) Version 15.1 implementation in June 2019. The broad scope of this implementation included a new dynamical core, changes to physics and data assimilation. This was matched by an unprecedented amount of system evaluation and accomplished on a very tight schedule. We will discuss some of the feedback on this process and how that is expected to shape future transition of UFS codes to operations.