SUEWS v2026.1.28: QGIS Stability Improvements

Announcements
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A new version of SUEWS is now available, focusing on stability and bug fixes.

Highlights:

  • QGIS/UMEP stability — Fixed crash issues that caused QGIS to fail mid-run. This was a significant pain point for many users.
  • Biogenic CO2 fix — FcRespi now correctly uses local climate rather than global average temperature.
  • CO2 flux NaN fix — Resolved uninitialised NumCapita causing NaN values in output.
  • Pandas 3.0 ready — Forward compatibility for upcoming pandas release.

No breaking changes — full backward compatibility with v2025.11.20.

Install/upgrade:

pip install --upgrade supy

Full release notes: Release SUEWS v2026.1.28: QGIS Stability Improvements · UMEP-dev/SUEWS · GitHub

1 Like
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See issue: Unable to install 2026.1.28 in OsGeo environment · Issue #1180 · UMEP-dev/SUEWS · GitHub

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Thanks for flagging this, Fredrik.

For Windows QGIS/UMEP users: the OSGeo environment bundled with QGIS pins numpy to version 1.26.x,
which conflicts with the standard v2026.1.28 release (which requires numpy 2.0+). A dedicated build 2026.1.28rc1 is available with numpy<2.0 compatibility for this environment.

Users don’t need to manage this manually. The UMEP plugin will handle dependency resolution automatically, selecting the appropriate version based on the environment (I’ll do a PR for umep-reqs shortly).

Standalone Python users (outside QGIS) should use v2026.1.28 directly.

1 Like
4

Thanks for flagging this, Fredrik.

For Windows QGIS/UMEP users: the OSGeo environment bundled with QGIS pins numpy to version 1.26.x, which conflicts with the standard v2026.1.28 release (which requires numpy 2.0+). A dedicated build — v2026.1.28rc1 — is available with numpy<2.0 compatibility for this environment.

Users don’t need to manage this manually. The UMEP plugin will handle dependency resolution automatically, selecting the appropriate version based on the environment.

Standalone Python users (outside QGIS) should use v2026.1.28 directly.

1 Like