Weather models, compared
These are the open physics models run by national weather agencies and ECMWF. Here is who runs each one, how they differ, and how they scored when we tested them against the weather that actually happened. When they line up they are reliable; when they split, the day is genuinely uncertain.
The big weather apps (Apple Weather, AccuWeather, The Weather Channel) do not publish exactly how their forecasts are made, so we grade the open models directly. The European model (ECMWF) is generally the most accurate global model and tops several of our tested scoreboards, but no model wins everywhere - so we grade them country by country and show them side by side.
European · ECMWF IFS
Widely regarded as the world's most accurate global model. Run by a 35-nation European agency, its high-resolution forecast is the benchmark others are measured against.
American · NOAA GFS
The United States' flagship global model, fully open and updated four times a day. Windy offers it alongside ECMWF and ICON.
German · DWD ICON
Germany's national model, known for sharp handling of European and mid-latitude weather. Open data, and a favourite third option on power-user tools.
Met Office · UKMO Unified Model
Britain's own national model, run by the Met Office. Strong over the UK and North Atlantic.
Env. Canada · ECCC GEM
Canada's national model, built for a country of extreme cold snaps and fast-moving systems. Published as open data by Environment Canada.
NWS · NWS National Blend of Models
The official US statistical blend that fuses many models into one gridded forecast. NWS forecasters use it as the starting point for their official gridded forecast.