Expansion of UFS Hierarchical System Development: New Idealized Test Case Added to the UFS Weather Model

[jdkublnick]

The NOAA Earth Prediction Innovation Center (EPIC) is pleased to announce the addition of a new idealized, regional tropical cyclone test case into the UFS Weather Model's (UFS-WM) tests-dev framework in support of UFS hierarchical system development. The capability was developed by Weiguo Wang of NOAA's National Weather Service (NWS) Environmental Modeling Center (EMC), with contributions from Bin Liu and Zhan Zhang. Integration of the case was performed by EPIC, with scientific and technical support from NOAA's NWS EMC.

The case is based upon the I-HAFS configuration (Wang et al., 2024) and is designed to support controlled studies of tropical cyclone dynamics and forecast development. This case excludes real-world data assimilation and ocean coupling, and focuses solely on atmospheric forecasts using idealized inputs.

Initial and lateral boundary conditions (ICs/LBCs) for the test case are derived from a large-scale, idealized global Finite-Volume Cubed-Sphere (FV3) based atmospheric forecast. The initial vortex is constructed using the Reed and Jablonowski (2011) method, introducing a weak, balanced storm into an environment favorable for rapid intensification. The case is configured to run at 4-km resolution, with 81 vertical levels, and utilizes the FV3_HAFS_v1_thompson_nonsst physics suite from the Community Common Physics Package (CCPP); documentation on the physics suite, developed by the Developmental Testbed Center (DTC), is available on DTC's website. The forecast is initialized on 24 August 2019, and ICs/LBCs are provided for up to a five-day forecast duration. Input and fix file data for the test case is available via an S3 bucket and is pre-staged on all EPIC-supported Tier-1 platforms.

Users can find more information about the case configuration and how to run it on EPIC-supported Tier-1 platforms and via container in the HSD section of the updated UFS WM User's Guide.