There is no defensible single accuracy score for Windfinder at every spot. To judge it for your sessions, compare forecasts saved before the session with observations from a relevant station. Keep the model, lead time and measurement consistent.
Start with the feature you need
Windfinder provides weather information for planning; consult its official help for the forecast and observation products available at your location. Check whether the number on screen is a forecast or an observation before comparing it with another app.
A forecast describes expected conditions for a time in the future. An observation records conditions at a sensor. Neither automatically represents the wind at a nearby beach, harbour entrance or launch with different exposure.
A practical local accuracy check
- Choose a relevant station. Check the sensor location, exposure and update time. A sheltered harbour station may not represent open water.
- Save the forecast in advance. Record the model, issue time, forecast time, speed, gust and direction. Checking a forecast after it updates is not a fair test of what it predicted earlier.
- Match the time and units. Avoid comparing a gust with an average or a local-time forecast with a UTC observation.
- Repeat across several weather patterns. One missed thermal or one accurate afternoon cannot establish which model performs best.
- Record the decision that matters. For example: did it correctly predict whether your chosen riding window would occur? Keep that separate from exact speed error.
For a simple record, use these columns:
| Forecast issued | Forecast valid | Model | Predicted wind | Observed wind | Station / exposure notes |
|---|---|---|---|---|---|
| Save before the session | Match observation time | Record selected model | Keep units consistent | Same variable and interval | Note missing or stale data |
This is a suggested method, not a published WindUp performance study. We have not established that Windfinder is a fixed percentage accurate or that one app wins at your location.
Why the forecast and station can disagree
Terrain, sensor exposure, forecast resolution and the timing of local weather changes can all affect the comparison. A station discrepancy is useful evidence to investigate; it is not proof that the forecast is bad or the station is correct for every nearby spot.
Review the broader forecast even when the current observation looks suitable. The latest reading does not describe what will happen later in your session.
When a station alarm is the useful addition
If the forecast is adequate but you keep refreshing current readings, an alarm may solve a different problem. WindUp monitors supported stations against your chosen conditions. Check the station coverage first, then set the alarm in the app.
The live wind alarm is free. On iOS, Critical Alerts need permission to sound through Silent or Focus; connection and device settings affect delivery. An alert is a prompt to review conditions, not a guarantee that a session is suitable.
Compare alternatives to Windfinder if you need a different workflow, or download WindUp to check supported stations. For a related comparison, see how to assess Windy accuracy.
