# ECMWF IFS Ensemble

The ECMWF IFS Ensemble (ENS) produces 51 forecasts — one control run and 50 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)
* Six-hourly time steps
* Real-time data access via [Python SDK](https://docs.jua.ai/python-sdk/weather/forecast) or [REST API](https://docs.jua.ai/api-v2/getting-started)

## Technical Specifications

### Available Weather Parameters

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

| Code    | API Name                                           | Description                       | Units        |
| ------- | -------------------------------------------------- | --------------------------------- | ------------ |
| 2t      | air\_temperature\_at\_height\_level\_2m            | Air temperature at 2m             | Kelvin       |
| 2d      | dew\_point\_temperature\_at\_height\_level\_2m     | Dew point temperature at 2m       | Kelvin       |
| skt     | surface\_temperature                               | Surface Temperature               | 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        |
| 10fg    | wind\_speed\_of\_gust\_at\_height\_level\_10m\_max | Maximum wind gust at 10m          | 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 |
| sp      | surface\_air\_pressure                             | Surface Pressure                  | Pa           |
| 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        |

## Hindcast Data

**Data Access:** Hindcasts are available via [API](https://docs.jua.ai/api-v2/getting-started) or [SDK](https://docs.jua.ai/python-sdk/getting-started). 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  |