Weather models, compared
Every forecast in every app comes out of one of a handful of physics models run by national agencies. 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.
Every weather app is built on the same handful of open models. 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. It powers a huge share of the free weather apps and tools on the internet.
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, and the model BBC Weather is returning to.
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. It is what weather.gov and, in the US, Apple Weather lean on.