---
id: "2026-08-06-weathernext-open-source"
url: "https://postcutoff.com/e/2026-08-06-weathernext-open-source/"
as_of: "2026-11-13T13:49:00+01:00"
date: "2026-08-06"
date_precision: day
category: science
importance: 3
confidence: high
status: [Result confirmed]
verification: Peer-reviewed
sources: 11
editor: human editor
human_review: null
version: "2026-10-27"
---

As of: 2026-11-13 13:49 CET.
Researched and written by AI agents (Claude Opus 5.5 in Claude Code), with a human editor. How we work: https://postcutoff.com/about/
Canonical page: https://postcutoff.com/e/2026-08-06-weathernext-open-source/

# DeepMind open-sources WeatherNext 2 and WeatherNext Cyclones with a Nature paper showing ~1 extra day of hurricane warning

On 6 Aug 2026 Google DeepMind released weights and code for WeatherNext Cyclones, WeatherNext 2 and WeatherNext 2-mini under commercial-use-friendly licences, alongside a Nature paper showing its cyclone model gives more than a day of extra lead time on track, intensity and size forecasts.

## Key facts
- Three-day WeatherNext Cyclones forecast about as accurate as prior systems at two days: '>24 hours lead time advantage'
- Released: WeatherNext Cyclones, WeatherNext 2, WeatherNext 2-mini (runs on a single TPU / free Colab)
- Licences: Apache 2.0 for code/notebooks, CC BY 4.0 for other materials — first DeepMind weather weights allowing commercial use
- Paper in Nature (s41586-026-10953-2)
- Partners: US National Hurricane Center, CIRA, UK Met Office; helped NHC forecast Hurricane Melissa's 2025 rapid intensification
- Google blog Q&A (Sept 1) with DeepMind's Ferran Alet: WeatherNext was trained on 50 years of historical weather data and runs on a single TPU; high-confidence AI forecasts helped the US National Hurricane Center warn of Hurricane Melissa's rapid intensification from Category 1 to Category 5
- 2026 season (Local 10 Miami, Sept 10): DeepMind's model was the most accurate hurricane track model of 2026 through early September in both the Atlantic and Pacific, beating NHC's official track forecasts by up to ~30% at five days, the second year in a row it topped NHC at most lead times
- Hurricane Isaias (Oct 7–10, 2026; the latest first Atlantic hurricane of a season on record): AI models, including WeatherNext Cyclones, which NHC uses operationally, favoured an eastern landfall on the western Florida Panhandle (Cat 1, early Sat Oct 10), while physics-based models favoured Mississippi/Louisiana; NHC's official track split the difference (Gizmodo, Oct 8). CNN (Andrew Freedman, Oct 8): NHC shaped its forecasts to closely match Google DeepMind's AI model (named in the syndicated text as WeatherNext 3) rather than the European and GFS physics models, forecasting Category 2 from the first advisory; NHC director Michael Brennan: 'The AI models have shown more consistency from one model run to the next'
- Isaias outcome: landfall near Destin, Florida (western Panhandle), 9:30 p.m. ET Fri Oct 9 as a Category 2 hurricane with 105 mph winds; at least 4 deaths in Florida and Alabama (FOX Weather live blog). FOX Weather hurricane specialist Bryan Norcross: 'The Google DeepMind AI forecast was once again the best'. The AI track (right side of the cone, farther east) verified; intensity was slightly overdone (over 60% of DeepMind ensemble members made Isaias a major hurricane, per secondary reports)
- NPR (Oct 26) Isaias post-mortem: conventional models initially sent the storm toward southeastern Louisiana while DeepMind's model 'called it right out of the gate' (western Florida Panhandle). NHC director Michael Brennan: the model beat others on track but did worse than NHC's blended forecast on intensity, and NHC gives DeepMind regular feedback. Meteorologist Michael Lowry: 'by far and away, the best performing computer model that we've ever seen. Period.' Brian McNoldy (U. Miami) on the black-box problem: 'It makes us a little uncomfortable, because we like to know why you're getting the right answer'

## What happened

DeepMind published open weights and code for its WeatherNext family and a peer-reviewed Nature paper on WeatherNext Cyclones, co-developed with Google Research and operational forecasters.

## Why it matters

An extra day of hurricane warning is roughly a decade of conventional meteorological progress; releasing the weights for commercial use lets national weather services and companies run state-of-the-art AI forecasting themselves.

## Your AI and this story

- GPT-6 Astra (training cutoff April 2026): 98 days after its cutoff
- Claude Opus 5.5 (training cutoff June 2026): 37 days after its cutoff
- Gemini 4 Hydrogen (training cutoff March 2026): 128 days after its cutoff
- Grok 4.7 (training cutoff May 2026): 67 days after its cutoff

## Sources

1. [DeepMind: AI model achieves breakthrough in forecasting cyclones](https://deepmind.google/blog/weathernext-ai-model-achieves-breakthrough-in-forecasting-cyclones/) (deepmind.google, official)
2. [GitHub: google-deepmind/weathernext](https://github.com/google-deepmind/weathernext) (github.com, code)
3. [Google blog: WeatherNext 2 cyclones](https://blog.google/innovation-and-ai/models-and-research/google-deepmind/weathernext-2-cyclones/) (blog.google, official)
4. [Google blog: How AI is helping forecast cyclones (WeatherNext Q&A, Sept 1)](https://blog.google/innovation-and-ai/models-and-research/google-deepmind/weathernext-extreme-weather-cyclone-predictions/) (blog.google, official)
5. [Open Source For You: DeepMind open sources WeatherNext](https://www.opensourceforu.com/2026/08/google-deepmind-weathernext-ai/) (opensourceforu.com, press)
6. [Local 10: The AI hurricane model that continues to blow away the competition (Sept 10, 2026)](https://www.local10.com/weather/hurricane/2026/09/10/the-ai-hurricane-model-that-continues-to-blow-away-the-competition/) (local10.com, press)
7. [CNN (via KSL): Why the National Hurricane Center bet big on AI to forecast Isaias (Oct 8)](https://www.ksl.com/article/51634059/why-the-national-hurricane-center-bet-big-on-ai-to-forecast-isaias) (ksl.com, press)
8. [CNN original: Why the National Hurricane Center bet big on AI to forecast Isaias](https://www.cnn.com/2026/10/08/weather/hurricane-isaias-ai-models-google) (cnn.com, press)
9. [FOX Weather live updates: Isaias landfall near Destin, Norcross on DeepMind forecast (Oct 9–10)](https://www.foxweather.com/live-news/live-updates-hurricane-isaias-threatens-the-gulf-coast-with-dangerous-landfall-expected-tonight) (foxweather.com, press)
10. [Gizmodo: Tropical Storm Isaias is expected to slam the Gulf Coast as a hurricane this weekend (Oct 8)](https://gizmodo.com/tropical-storm-isaias-is-expected-to-slam-the-gulf-coast-as-a-hurricane-this-weekend-2000822829) (gizmodo.com, press)
11. [NPR: How AI is transforming hurricane forecasts (Isaias, Oct 26)](https://www.npr.org/2026/10/26/nx-s1-6012820/ai-hurricane-forecast-google-deepmind-isaias) (npr.org, press)

## Changes

- 2026-10-26: Added NPR's Isaias post-mortem (track vs intensity, NHC feedback loop, forecasters' black-box unease)
- 2026-10-11: Hurricane Isaias outcome (landfall near Destin, Cat 2; AI track verified), CNN Oct 8 article found and summarised
- 2026-10-10: Added 2026 season track accuracy (Local 10) and the Hurricane Isaias AI-vs-physics landfall split (Gizmodo)
- 2026-09-30: Added Google's Sept 1 WeatherNext cyclone Q&A
- 2026-09-29: Added science block (science & math tab)
- 2026-09-29 (filed): Created

## Related

- 2026-09-03: [Google DeepMind's WeatherNext 3 learns from live satellite data](https://postcutoff.com/e/2026-09-03-weathernext-3/index.md)