Recast WOOF

Weather Observations and Open Forecasting: a GPU-native weather model you run on your own card.

WOOF is a regional weather model with WRF-class physics that runs on one NVIDIA GPU, with its own preprocessing, data assimilation and plots. One install carries three models:

Preview means the model is in the package, documented and tested on CPU, and its command says preview each time it runs; its config and checkpoint formats may change in a minor release. The major-version promise covers the regional model.

Install

Linux on x86_64, Python 3.11 or newer, an NVIDIA GPU and driver. 1.0.0 has no Windows build of the native tools.

python3 -m venv ~/woof-env
~/woof-env/bin/python -m pip install 'recast-woof[all-cu12]'
~/woof-env/bin/woof fetch-tables
~/woof-env/bin/woof fetch-geog --datasets wrf
~/woof-env/bin/woof doctor

For a CUDA 13 setup use all-cu13. The hex model runs only on CUDA 13, so install all-cu13 to use it. Install one CuPy/CUDA major per environment. The Linux wheel carries the native tools (GRIB and NetCDF decoding, the WPS-equivalent preprocessor, the renderer).

fetch-geog downloads the global geography every forecast builds its terrain, land use and soil from: about 1.3 GB, 17 GB unpacked, once per computer. fetch-tables adds two Thompson microphysics tables (about 314 MiB). Reference tables and map assets arrive with the recast-woof-data package.

Run a forecast

woof domain --point 35.3,-97.5 --source hrrr --cycle latest --hours 3 \
     --root-dx 3 --point-extent-km 300 --out forecast.toml
woof go forecast.toml --dry-run
woof go forecast.toml

--dry-run reviews the route, sizes it for your card and names anything missing; the second line fetches, prepares, runs and draws. Pictures are drawn as each history frame lands, beside the running forecast.

Compare two runs, any product, as run A minus run B:

woof render --diff runA/ runB/ --out diff/

The pair must share the grid and the valid times; a mismatch is refused by name.

Documentation

• docs/public/: the CLI manual, physics, verification record, hardware guidance and data sources.
• components/hex/ and components/globe/: the hex and global models' manuals, tests and tools.
• woof --help-all lists every command; woof hex --help and woof global --help list the preview models' commands.

Science and limits

WOOF implements a WRF-ARW-class regional model and WRF-derived physics on the GPU. Its numerical comparisons apply to documented configurations and test cases; they do not establish general equivalence with WRF or forecast skill for every combination of physics, input data and hardware. The hex model is a port of the MPAS-A v8.4.1 dynamical core with this engine's physics; it is not MPAS and is not endorsed by UCAR. Use official meteorological services for forecasts and warnings.

WOOF 1.0.0 continues an engine released before under another name: it is that engine's release 2.8.0 and the fixes made since, under the WOOF name, with the hex and global models inside it. Settings spelled GPUWM_* keep working beside the new WOOF_* spelling.

Licence

Apache License 2.0. Third-party code, tables and datasets keep their own terms; see NOTICE and licenses/.