Upstream icon codes are useful keys, not the artwork. Meridian maps OpenWeather condition IDs to local Meteocon-style SVGs so cards stay sharp on retina screens and keep working offline once assets are cached.
Condition icons (clear, rain, thunder) sit beside metric glyphs for humidity, wind, UV, and pressure. Keeping both families in `/public/weather-icons` avoids a third-party CDN hop on every city card.
When OpenWeather adds or renames codes, the mapping layer is the single place to update — UI components keep consuming a stable local name. Missing codes fall back to a neutral cloudy mark rather than a broken image.
The goal is glanceable weather in the same visual language across hero, grid, and city detail — not pixel-perfect clones of OpenWeather’s raster sprites.
