What weather model does Australia use?
Australia runs its own forecast model — ACCESS — at global, regional and city scales. Here's what it is, where it comes from, and why you can't see it on Windy.
Australia's official forecasts come from the Bureau of Meteorology, which runs its own weather model called ACCESS — the Australian Community Climate and Earth-System Simulator. It is built on the UK Met Office Unified Model and runs as a family: a global version (ACCESS-G), higher-resolution regional and city configurations, and a dedicated tropical-cyclone set-up. Every BOM forecast you read starts here.
What is ACCESS?
ACCESS is a numerical weather prediction (NWP) system. In plain terms, it takes millions of observations — from satellites, weather balloons, aircraft, ships, buoys and automatic weather stations — builds the best possible snapshot of the atmosphere right now, then solves the equations of fluid motion and thermodynamics forward in time on a supercomputer. The output is the grid of temperature, wind, pressure, cloud and rain that Bureau meteorologists interpret into the seven-day forecast on the BOM website and app.
The name reflects its ambition. ACCESS is not only a weather model; the same underlying framework underpins Australian climate and earth-system research. For day-to-day forecasting, the relevant part is the atmospheric NWP configuration.
The ACCESS family: one model, several resolutions
There is no single "ACCESS". The Bureau runs several configurations at different resolutions, each suited to a different job:
- ACCESS-G (Global) — covers the whole planet at roughly 12 km grid spacing. This is the backbone for medium-range forecasting across Australia and its vast marine zones.
- Regional and city models — higher-resolution domains nested over Australia and the capital cities. Finer grids resolve coastlines, ranges and sea breezes far better than a global model can, which matters enormously for places like Sydney, Melbourne and Perth.
- Cyclone configuration — a version run to support tropical-cyclone forecasting in the Australian region during the November-to-April season.
Coarser global grids see the big picture; finer nested grids see your suburb. Bureau forecasters blend them, along with international models, to produce the official product.
Where ACCESS comes from
ACCESS is based on the Unified Model developed by the UK Met Office, adapted and run by the Bureau for the Australian region and the Southern Hemisphere. That heritage is worth knowing: it means Australia's national model shares deep engineering roots with one of the world's leading forecasting systems, tuned for local conditions such as the subtropical ridge, Southern Ocean cold fronts and the tropical north.
It is a genuinely national capability. Running a global NWP system in-house puts Australia in a small club of nations — most countries rely entirely on models imported from elsewhere.
Why can't I see ACCESS on Windy or other apps?
Here is a common source of confusion. You can load ECMWF, GFS and ICON on Windy, but not ACCESS. That is because the Bureau does not publish ACCESS as a freely available open gridded feed in the way the European Centre and NOAA release their models. ECMWF and NOAA distribute open data that third-party sites can ingest; BOM largely delivers ACCESS output through its own products — MetEye, the app, forecasts and warnings — rather than as raw GRIB files.
The practical upshot: to see the Australian model, use BOM directly. To compare the global heavyweights against each other, use a tool built for that. This is the exact niche checkweather.io fills — because it cannot show ACCESS either, it lines up ECMWF, GFS and ICON side by side, scores how much they agree, and links back to BOM for the authoritative Australian view.
ACCESS vs the global models: how do they compare?
| Model | Run by | Approx. global resolution | Openly available? |
|---|---|---|---|
| ACCESS-G | Bureau of Meteorology (Australia) | ~12 km | No open gridded feed |
| ECMWF (IFS/HRES) | European Centre (Europe) | ~9 km | Open data available |
| GFS | NOAA (United States) | ~13 km | Fully open |
| ICON | DWD (Germany) | ~13 km | Open data available |
No model is best at everything. ECMWF is generally rated the strongest global performer; ACCESS has the advantage of high-resolution configurations tuned specifically for the Australian region and is the basis of the warnings that emergency services act on. Good forecasters do not pick one — they weigh several.
How ACCESS turns data into your forecast
It is worth understanding the pipeline, because it explains why the Bureau's forecast is more than a computer printout. First, data assimilation blends millions of fresh observations into the best estimate of the atmosphere's current state — the model's starting point. Then the model integrates the equations of motion forward, hour by hour, producing grids of pressure, wind, temperature, humidity, cloud and rainfall. Finally, Bureau meteorologists interpret and adjust that raw output, adding local knowledge and cross-checking against international models, before it becomes the seven-day forecast, the marine forecast, or a Severe Weather Warning.
Higher-resolution ACCESS configurations feed the detail — the timing of a southerly buster along the New South Wales coast, a sea breeze cooling Perth, orographic rain banking up against the Great Dividing Range — while the global model anchors the big synoptic picture. This layering is why an ACCESS-based forecast can be both broad and locally specific at once.
Where ACCESS is strongest — and where it struggles
ACCESS is at its best with large, well-organised weather systems: cold fronts marching up from the Southern Ocean, high-pressure ridges parking over the continent, and the broad steering of tropical systems in the north. Its Australia-focused, high-resolution grids give it a genuine edge over generic global models for coastal and terrain detail.
Like every model, it finds the same things hard that all models find hard: individual summer thunderstorms, the exact intensity of a tropical cyclone, and fine-scale rainfall totals from convection. These are limits of physics and resolution, not of ACCESS specifically — which is precisely why forecasters never rely on a single model in these situations.
Does the Bureau only use ACCESS?
No, and this is important. BOM meteorologists routinely consult international guidance — ECMWF in particular — alongside their own ACCESS output. The official forecast is a human-quality-controlled blend of models, local knowledge and observations, not a raw dump from a single computer. When ACCESS and ECMWF disagree on Friday's front, a forecaster's judgement decides the wording you eventually read.
The takeaway
The model behind Australia's weather is ACCESS, the Bureau's own system with UK Met Office roots, run at global, regional and city scales plus a cyclone configuration. You won't find it on consumer apps because it isn't released as open data — so use BOM for the Australian model, and use a multi-model comparison for everything else.