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A weather app that tells you what matters: how today compares to yesterday.
Inspired by this tweet from @genmon:
Why doesn't my weather app tell me the weather yesterday? I can never plan based on numerical temperature, wind etc. Too much thought. All I want is to see: oh yeah like yesterday but a little warmer. And I know what I wore yesterday so I can adjust easily.
Rendering mermaid diagram...
- Uses browser geolocation to find you automatically
- Fetches from Open-Meteo (free, no API key needed) with
past_days=1andforecast_days=2 - Generates a natural language comparison like "A touch warmer than yesterday, and drier"
- Shows a side-by-side hourly chart overlaying yesterday and today
- Every detail card includes a relative comparison to yesterday
- Yesterday / Today / Tomorrow at a glance
- Hero comparison sentence — the main event
- Hourly temperature overlay chart with current-hour indicator
- Rain, wind, conditions — all compared to yesterday
- °C / °F toggle
- Reverse geocoded location name
- Staggered fade-in animations
- Mobile-responsive
- Frontend: React 18, Canvas API for the chart
- Backend: Hono on Val Town
- Data: Open-Meteo (free, open-source weather API)
- Geocoding: OpenStreetMap Nominatim
- Fonts: Instrument Serif + DM Sans