1.5 km High-Resolution Forecasts for Central Europe
1.5 km High-Resolution Forecasts for Central Europe
MeteoFrance API with ARPEGE and AROME models
The next set of high-resolution weather models is now available. 1.5 km resolution AROME and global ARPEGE models from MeteoFrance are now integrated in the Open-Meteo MeteoFrance API.
The API offers time-series of weather forecasts for up to 4.5 days and integrates 4 different weather models:
Arpege World: MeteoFrance global weather model at 55 km resolution with 3-hourly data and up to 4.5 days forecast
Arpege Europe: European model that includes North Africa, Iceland, the entire Mediterranean and Black Sea at 11 km resolution with 1-hourly data.
Arome France: Central European model at 2.5 km resolution that covers France Germany, Spain and UK
Arome France HD: 1.5 km resolution model that covers a slightly larger region than Arome France, but offers fewer weather variables.
As typical for high-resolution local models, the forecast length is only 1.5 days, but afterwards forecast uncertainty outweighs benefits from high-resolution anyway.
1.5-km resolution models certainly look stunning. The map below shows night time temperatures in Central Europe. The Mediterranean Sea preserves temperatures of 22°C while the mainland cools down to 12°C. The little streams in the south of France show how colder air flows from the mainland to sea at night.
At a higher zoom, more details are visible like structures in the alpine valleys or the metropolitan area of Milan that heats up more quickly than the surroundings of Northern Italy.
Higher resolution weather models do not necessarily increase forecast quality. Weather is mostly driven by large scale patterns that span hundreds of kilometres, like warm and cold fronts. Higher resolution can however improve local temperature, wind and thunderstorm forecasts because terrain and land-type are better represented.
Available weather variables and data
The new Open-Meteo MeteoFrance API includes most weather variables that are available from MeteoFrance:
Temperature, humidity, dew point
Precipitation and snowfall
Sea level and surface level pressure
Cloud-cover on low, medium and high altitudes
CAPE, Evapotranspiration, Vapour Pressure Deficit
Solar radiation (note: diffused and direct radiation use a separation model)
29 Pressure levels with temperature, humidity, cloud-cover and wind
Data is archived starting from 16. September 2022 and is now continuously being updated. In one API call you can get past and forecast.
All 4 MeteoFrance models are transparently integrated and depending on the location the best available model is chosen. For Europe and Northern Africa forecast quality should be very high. For other parts of the world, only the MeteoFrance global weather model is used, with only 55 km resolution.
For most cases, the regular weather forecast API is recommended and will automatically fetch the best available data for any location worldwide.
With the addition of MeteoFrance and previously GFS, Open-Meteo covers now Europe and America with high resolution data. For Asia only 11-km resolution models are available, but hopefully more open data will be available soon.
If you would like to get more open data weather datasets integrated, please leave a comment! A lot of time is spent in researching new data sources with good quality and it is hard to find local weather models.