> For the complete documentation index, see [llms.txt](https://docs.jua.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.jua.ai/models-and-products/third-party-models/ecmwf-ens.md).

# ECMWF IFS Ensemble

The ECMWF IFS Ensemble (ENS) provides 50 perturbed-forecast runs with slightly varied starting conditions.

## Live Forecast Data

* Global coverage at 25 km resolution (720x1440 grid)
* Four daily runs (00, 06, 12, 18 UTC)
* 00/12 UTC runs: 360h forecast (15 days); 06/18 UTC runs: 144h forecast (6 days)
* 3-hourly time steps to 144h, then 6-hourly out to 360h
* Real-time data access via [Python SDK](/python-sdk/weather/forecast.md) or [REST API](/api-v2/getting-started.md)

## Technical Specifications

### Available Weather Parameters

ECMWF ENS uses standardized variable naming conventions. For full details on the naming structure, see [Weather Variable Naming](/python-sdk/weather/naming.md).

| Code    | API Name                                       | Description                            | Units        |
| ------- | ---------------------------------------------- | -------------------------------------- | ------------ |
| 2t      | air\_temperature\_at\_height\_level\_2m        | Air temperature at 2m                  | Kelvin       |
| 10si    | wind\_speed\_at\_height\_level\_10m            | Horizontal wind speed at 10m           | m s⁻¹        |
| 100si   | wind\_speed\_at\_height\_level\_100m           | Horizontal wind speed at 100m          | m s⁻¹        |
| 10wdir  | wind\_direction\_at\_height\_level\_10m        | Horizontal wind direction at 10m       | Degrees true |
| 100wdir | wind\_direction\_at\_height\_level\_100m       | Horizontal wind direction at 100m      | Degrees true |
| msl     | air\_pressure\_at\_mean\_sea\_level            | Mean Sea-level Pressure                | Pa           |
| tp      | precipitation\_amount\_sum\_1h                 | Total Precipitation                    | mm m⁻²       |
| ssrd    | surface\_downwelling\_shortwave\_flux\_sum\_1h | Surface solar downward irradiance      | J m⁻²        |
| z       | geopotential\_at\_pressure\_level\_50000Pa     | Geopotential at 500 hPa pressure level | m² s⁻²       |

## Hindcast Data

**Data Access:** Hindcasts are available via [API](/api-v2/getting-started.md) or [SDK](/python-sdk/getting-started.md). For bulk, grid-based access, please contact <support@jua.ai>.

| **Model** | **Spatial Extent**                       | **Temporal Extent** |
| --------- | ---------------------------------------- | ------------------- |
| ECMWF ENS | Global, 25 km resolution (720x1440 grid) | 2025-09-01 - today  |


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