Point sampling
The value is taken from the model’s own grid and the sampling method is recorded. No height correction is applied silently.
Lead-time ladder
The same valid time is viewed from the T+6, T+12, T+24 and T+48 runs, so you see how forecast skill changes with lead time.
Time alignment
Forecast and observation are matched at the exact valid time, with zero tolerance. Nearby timestamps are not silently substituted for exact observation times; an unmatched sample stays out, with its reason recorded.
Uncertainty
The range between models is shown openly. Agreement between models is not presented as a probability.
Metrics
Mean error, mean absolute error and root-mean-square error — by lead time, station and model. Missing data are not treated as zero.
No ranking
Models are not ranked until a verification campaign is complete and its results are published.
- e = F − O
- forecast minus observation
- Bias = (1/n) Σ e
- mean error
- MAE = (1/n) Σ |e|
- mean absolute error
- RMSE = √[(1/n) Σ e²]
- root-mean-square error
The canonical unit is the kelvin. Observations come from official national station networks: AEMET in Spain, Météo-France in France.
Verification campaign · 2 m air temperature
8stations×4lead times×3models×56runs
=5,376expected samples · 14 days
The campaign is a controlled pilot panel and makes no claim to represent a whole country. Its launch gates are being checked; results will be published when the campaign is complete.