Meteo Compare

MeteoCompare is the weather app for people who want to understand forecast reliability, not just consult it.

Instead of displaying a single forecast, MeteoCompare queries 17 reference weather models in parallel and shows you where they agree — and where they diverge.

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SUPPORTED MODELS

France
• AROME France HD (Météo-France, 1.5 km)
• AROME France (Météo-France, 2.5 km)

Europe
• ARPEGE Europe (Météo-France, 11 km)
• ICON-EU (DWD Germany, 7 km)
• ICON-D2 (DWD Germany, 2 km)
• MET Nordic (MET Norway, 1 km, Scandinavia)
• KNMI HARMONIE (Netherlands, 5.5 km)

Global
• ARPEGE World (Météo-France, 25 km)
• ICON (DWD Germany, 13 km)
• GFS (NOAA USA, 13 km, up to 16 days)
• HRRR (NOAA USA, 3 km, rapid-refresh continental US)
• ECMWF (European Centre, 25 km)
• ECMWF AIFS (European Centre, AI model)
• UKMO Global (UK Met Office, 10 km)
• GEM Global (ECCC Canada, 15 km)
• BOM ACCESS (Bureau of Meteorology Australia, 12 km)
• CMA GRAPES (China Meteorological Administration, 15 km)

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CONFIDENCE INDEX

A 0-100% score tells you how much the models agree:
• Perfect convergence → 95% (good confidence)
• Strong divergence → 30% (real uncertainty)

Weighting favors high-resolution models in their coverage zone (AROME in France, ARPEGE in Europe, HRRR in the US, MET Nordic in Scandinavia). Tap the confidence badge to open a "Why this confidence?" page that breaks down which model predicted what, variable by variable.

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PER-MODEL BIAS TRACKING

Every day, the app compares each model's past forecasts against actual observations (ERA5), for each of your favorite cities. Under each model name in the tables, a discreet pill tells you what you need to know:

• Red pill "+1.8°" — the model systematically overestimates temperature by 1.8° on average over 30 days
• Blue pill "−2.3 mm" — the model underestimates precipitation
• Neutral checkmark — the model is calibrated here, no mental correction needed
• Empty pill — not enough history yet (< 14 days of overlap)

Tap a pill to open a sheet with a 30-day chart overlaying forecast and observation, mean bias, standard deviation and a plain-language summary. The forecast data itself is never modified — only the context is enriched so you can interpret forecasts more accurately.

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VISUALIZATIONS

• Hourly confidence band over 7 days
• Three metrics on the confidence band: temperature, precipitation, wind
• 10-year climate normals overlay (dashed lines) to compare the forecast against typical values for the date
• Hourly / daily toggle
• Day × Model tables: temperature, precipitation, wind with direction arrows
• "%" badges under weather icons: rain probability or cloud cover depending on condition

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PRIVACY BY DESIGN

• Zero data collection
• No analytics, no tracking, no ads
• All data stays on your device
• Local-only storage (favorites, cache, preferences)
• Only external requests: Open-Meteo (free, no account)

The app requests exactly two permissions: INTERNET and ACCESS_NETWORK_STATE.

You can support the development of Meteo Compare by making a donation (go to the settings page in the app).

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MORE FEATURES

• Home screen widgets
• Favorite cities with daily quick view
• Model sorting in Settings by zone / family / resolution
• City search by name
• Offline cache (view last forecasts without network)
• Auto light/dark theme (Material You)
• Full TalkBack accessibility

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WEATHER DATA

Provided by Open-Meteo (https://open-meteo.com), free for non-commercial use. MeteoCompare is independent and not affiliated with Open-Meteo, Météo-France, NOAA, DWD, ECMWF, UK Met Office, ECCC, MET Norway, KNMI, BOM or CMA.