Models
Weather models explained
Every model is built for a purpose. Some cover the world for 16 days, some draw individual thunderstorms for the next 18 hours, and some blend many forecasts into one. These pages explain the models you can open in 4070, using specifications from the agencies that produce them, with strengths, limits and the tools that show each one. For a first read, start with how to read weather models.
The GFS weather model
NOAA’s Global Forecast System: a global model run four times a day out to 16 days.
The ECMWF IFS weather model
The Integrated Forecasting System from the European Centre for Medium-Range Weather Forecasts, often called the Euro, at about 9 km, with 10 days in open data.
The ECMWF AIFS weather model
ECMWF’s machine-learning forecast system, the AIFS: 15 days ahead, four runs a day, at about 0.25 degree.
The NOAA AI-GFS weather model
NOAA’s machine-learning global model, based on GraphCast, that became operational in December 2025 and forecasts 16 days ahead.
The HRRR weather model
NOAA’s High-Resolution Rapid Refresh: a 3 km model that starts a new run every hour and looks ahead 18 to 48 hours.
The NAM 3 km Nest weather model
The high-resolution nest of NOAA’s North American Mesoscale model, four runs a day out to 60 hours, and the model NOAA plans to replace with RRFS.
The National Blend of Models (NBM)
NOAA’s statistically processed blend of many models, hourly updated, with probabilities for snow, rain, temperature and wind out to 11 days.
The GEFS ensemble
NOAA’s Global Ensemble Forecast System: 31 versions of the GFS-style forecast, four times a day, used to see how confident a forecast can be.
The ECMWF EPS ensemble
The European global ensemble: 51 forecasts at about 9 km, out to 15 days, used to measure how much a forecast can change.
The CFSv2 climate model
NOAA’s Climate Forecast System, version 2: a coupled atmosphere, ocean, land and sea ice model used for subseasonal and seasonal outlooks.
See the models for yourself.
Model Explorer, Compare Models, soundings and plumes are part of 4070 Pro, with a seven-day free trial.