# NOAA puts AI global weather models into operation, led by a retrained GraphCast

Canonical page: https://technooptimist.io/stories/noaa-puts-ai-global-weather-models-into-operation-led-by-a-retrained-cb104e08
Date: 17 Dec 2025
About: [NOAA](https://technooptimist.io/companies/noaa.md) · [AIGFS](https://technooptimist.io/ai/aigfs.md)
Original source: https://www.noaa.gov/news-release/noaa-deploys-new-generation-of-ai-driven-global-weather-models

NOAA launched three operational AI forecast systems: AIGFS (one best-guess forecast), AIGEFS (a 31-member AI ensemble) and HGEFS (a 62-member hybrid of AI and physics runs). AIGFS started from Google DeepMind's GraphCast, fine-tuned on NOAA's own analyses. It matches or beats the physics GFS on large-scale patterns and storm tracks at a tiny fraction of the computing cost, but is weaker on hurricane intensity.

## Key facts

- A 16-day AIGFS forecast uses 0.3% of the physics GFS's computing and takes about 40 minutes.
- AIGEFS early results add 18 to 24 hours of useful forecast skill, at about 9% of the physics ensemble's compute.
- HGEFS beat both the AI-only and physics-only ensembles on most of NOAA's verification scores.
- Known weakness: v1.0 forecasts hurricane intensity worse than GFS; NOAA said later versions will fix it.

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