ECMWF vs GEM
ECMWF IFS (European model) and Canadian GEM (Canadian model) are independent forecasts built by different weather services. ECMWF: Large-scale pattern and storm track 3–10 days out, pressure systems, medium-range temperature. GEM: Winter storms and cold-air outbreaks in North America; HRDPS short-range detail. Neither is right every time: the useful signal is whether they agree. Compare them live below for any city.
| ECMWF IFS | Canadian GEM | |
|---|---|---|
| Run by | European Centre for Medium-Range Weather Forecasts | Environment and Climate Change Canada |
| Origin | Europe | Canada |
| Resolution | 9 km (IFS HRES) | ~15 km global; 2.5 km HRDPS over Canada |
| Model runs | 4 per day (00, 06, 12, 18 UTC) | 2 per day global |
| Forecast range | up to 15 days | up to 10 days |
| Type | Physics-based NWP | Physics-based NWP |
| Also called | European model, Euro, IFS, ECMWF HRES | Canadian model, CMC, GDPS, HRDPS |
| Strengths | Large-scale pattern and storm track 3–10 days out, pressure systems, medium-range temperature. | Winter storms and cold-air outbreaks in North America; HRDPS short-range detail. |
| Weaknesses | A 9 km grid still smooths narrow valleys and coastlines; convective showers are parameterised, not resolved. | Has a known tendency to over-forecast precipitation in some setups. |
Key differences
- ECMWF resolution: 9 km (IFS HRES); GEM: ~15 km global; 2.5 km HRDPS over Canada.
- ECMWF range: about 15 days; GEM: about 10 days.
- ECMWF updates: 4 per day (00, 06, 12, 18 UTC); GEM: 2 per day global.
- ECMWF weak spots: A 9 km grid still smooths narrow valleys and coastlines; convective showers are parameterised, not resolved. GEM weak spots: Has a known tendency to over-forecast precipitation in some setups.
Questions
Is ECMWF or GEM more accurate?
ECMWF IFS (European model) and Canadian GEM (Canadian model) are independent forecasts built by different weather services. ECMWF: Large-scale pattern and storm track 3–10 days out, pressure systems, medium-range temperature. GEM: Winter storms and cold-air outbreaks in North America; HRDPS short-range detail. Neither is right every time: the useful signal is whether they agree. Compare them live below for any city.
Which is the European model and which is the American model?
The "European model" is ECMWF (IFS, and its AI sibling AIFS). The "American model" is NOAA's GFS. The German model is ICON, the Canadian model GEM, the UK model UKMO and the French models ARPEGE/AROME.
Where can I see ECMWF and GEM side by side?
On every MeteoStack city page: the stack shows ECMWF, GEM and up to ten other models hour by hour, with their median consensus, spread and rain odds. It is free and works for any place on Earth.
More comparisons
ECMWF vs GFS · ECMWF vs ICON · GFS vs ICON · ECMWF vs AIFS · ECMWF vs UKMO · GFS vs GEM · ECMWF vs GEM · ICON vs ARPEGE · GFS vs AIFS · UKMO vs GFS · ECMWF vs JMA · ICON vs UKMO · ECMWF vs ARPEGE · GFS vs JMA