Dataset
ERA5 Historical Weather Data
ERA5 is a reanalysis dataset for historical weather backtesting, solar and wind resource assessment, and energy modelling. Yun-Meng Weather API exposes common fields by latitude and longitude so teams can use them in forecasting models, project reports and research workflows.
Spatial and Temporal Resolution
- Spatial resolution
- 0.25° × 0.25°
- Temporal resolution
- 1 hour
- Typical use cases
- Backtesting, resource assessment, model training
- Temporal Coverage
- 1940 to present
Variable Table
| Field | Name | Unit | Description |
|---|---|---|---|
| tas | Air temperature | K / °C | Near-surface air temperature for load, PV efficiency and comfort analysis. |
| hurs | Relative humidity | % | Near-surface relative humidity for weather features and environmental corrections. |
| sp | Surface pressure | Pa | Surface pressure for air density, wind power and weather normalization. |
| pr | Precipitation | m / mm | Hourly precipitation for site operations, icing and weather event detection. |
| uas | Near-surface U wind | m/s | East-west wind component that can be combined with vas for wind speed and direction. |
| vas | Near-surface V wind | m/s | North-south wind component that can be combined with uas for wind speed and direction. |
| ws | Wind speed | m/s | Near-surface wind speed for diagnostics and model inputs. |
| wd | Wind direction | degree | Wind direction angle for wind roses and resource analysis. |
| rsds | Global horizontal irradiance | W/m² | Core solar resource and PV power forecasting field. |
| dni | Direct normal irradiance | W/m² | Direct irradiance for solar modelling and concentrated solar use cases. |
| dhi | Diffuse horizontal irradiance | W/m² | Diffuse irradiance for sky-radiation decomposition and plane-of-array estimates. |
| u100 | 100m U wind | m/s | East-west 100m wind component for wind resource assessment. |
| v100 | 100m V wind | m/s | North-south 100m wind component for wind power features. |
| u10n | Neutral 10m U wind | m/s | East-west 10m wind component under neutral stability. |
| v10n | Neutral 10m V wind | m/s | North-south 10m wind component under neutral stability. |
Request Example
{
"lat": 31.7655,
"lon": 105.205,
"dataSourceId": "era5",
"stime": "2026-04-20 00:00",
"etime": "2026-04-21 23:00",
"fields": ["tas", "hurs", "ws", "rsds"],
"timezone": "8"
}Dataset FAQ
Is ERA5 suitable for real-time forecasting?
ERA5 is mainly used for historical backtesting and reanalysis. Forecasting scenarios should use the German Meteorological Agency (DWD) forecast dataset.
Can ERA5 fields be used directly in renewable energy models?
Yes, but production models usually combine ERA5 with station measurements, asset parameters, terrain features and data cleaning rules.
Validate ERA5 historical weather
Use a real latitude / longitude and a few fields to check whether ERA5 fits your model before integration.