Science
How does weather forecasting work?
Weather forecasting works by feeding huge amounts of current data — temperature, pressure, wind, humidity from satellites, stations, and balloons — into powerful computer models that simulate how the atmosphere will change over the coming hours and days.
See it in motion.
Watch a 2-minute animated lesson that shows exactly how weather forecasting works.
Step by step
- 1Sensors worldwide measure the current state of the atmosphere.
- 2Supercomputers run physics-based models to project changes forward.
- 3Forecasts get less accurate further ahead (the atmosphere is chaotic).
- 4Forecasters interpret model output and refine the prediction.
Frequently asked questions
- Why are forecasts sometimes wrong?
- The atmosphere is chaotic; tiny measurement gaps grow over time, so accuracy drops the further ahead you predict.
- How far ahead can we forecast weather?
- Fairly reliably about a week; beyond that, uncertainty rises quickly.
- What data goes into a forecast?
- Temperature, pressure, humidity, and wind from satellites, ground stations, balloons, and radar.