ArWen

ArWen 2.9.8

ArWen: GPU-native WRF-ARW-class regional weather model, verified against WRF v4.6.1

  • By Fahrenheit Research
  • Open Source
  • Updated Oct 26, 2026
Download for Windows

About ArWen

ArWen is an independent, GPU-native implementation of a WRF-ARW-class regional atmospheric model. It is not affiliated with or endorsed by NCAR or UCAR. The name is a wordmark for "the ARW solver, GPU-native"; the Python package is currently named gpuwm. Safety. ArWen is a research and educational tool. It is never a substitute for official forecasts and warnings from your national meteorological service. Do not use it to make safety decisions. Regional numerical weather prediction at convective scale has mostly required institutional clusters, which means most of the world runs on global-model guidance at 10-25 km. ArWen's aim is to put a verified, kilometer-scale limited-area model on a single consumer GPU: pick a point, size a nest ladder to your card, pull public analysis data, and run a 1 km (or 500 m) simulation of your own area on hardware you own -- especially in places where no national convection-permitting model exists.

What's new in 2.9.8

The desktop stays ArWen Desktop 1.0.10, from the 2.9.0 release.
Node GPU gate: Stage 1 and both GPU-shard results, with the tested source revision and card identity.

Fixed

  • A cycle younger than an archive holds (GDEX 48 h, NCEI 0.5 degree 72 h) is fetched from the next source instead of failing on the archive.
  • Ensemble members that share a download folder no longer rewrite each other's composed files (gem-gdps, ecmwf-open-data-0p1, GEFS).
  • Moving nest-downs finer than 4 km drop the parent's MM5-only surface-layer options with the parent's surface layer.
  • GOES-17 ABI windows (full disk and PACUS) fetch.
  • The radar-tendency receipt records a slot with no covered point.
  • rw_mpas_static builds global statics about twice as fast, with identical output.

Full release notes »

Technical details

PublisherFahrenheit Research
Version2.9.8
Release date2026-10-26
LicenseApache-2.0
Installer typezip
Architecturex64
Package IDFahrenheitResearch.ArWen

Links & install command

Install ArWen from the command line with Windows Package Manager (winget):

winget install --id=FahrenheitResearch.ArWen -e

Older versions

  • 2.9.7
  • 2.9.6
  • 2.9.5
  • 2.9.4
  • 2.9.3
  • 2.9.2
  • 2.9.0
  • 2.8.9
  • 2.8.7