How we measure accuracy
Every morning at 06:10 UTC we freeze each provider's forecast for the next 5 days. The next day we compare it with real observations (METAR from the reference airport, public domain). Metrics follow WMO/TD 1023: mean absolute error and bias of daily high/low, share of days within ±2 °C, contingency table for rain yes/no (≥ 0.1 mm or reported phenomenon), wind error. The baseline is persistence ("tomorrow like today"). 30-day scores need 30 days of data; rain scores need 90. No AI touches any value.
Cities
- Forecast accuracy for Warsaw
- Forecast accuracy for Krakow
- Forecast accuracy for Wroclaw
- Forecast accuracy for Lodz
- Forecast accuracy for Poznan
- Forecast accuracy for Gdansk
- Forecast accuracy for Szczecin
- Forecast accuracy for Lublin
- Forecast accuracy for Bydgoszcz
- Forecast accuracy for Bialystok
- Forecast accuracy for Katowice
- Forecast accuracy for Gdynia
- Forecast accuracy for Częstochowa
- Forecast accuracy for Sosnowiec
- Forecast accuracy for Radom
- Forecast accuracy for Mokotów
- Forecast accuracy for Gliwice
- Forecast accuracy for Rzeszów
- Forecast accuracy for Torun
- Forecast accuracy for Kielce