Turn your weather station into proactive smart home automations — not just numbers on a dashboard.
ws_core takes the ordinary temperature, wind, and rain sensors you already have in Home Assistant and turns them into a local weather intelligence engine. It watches your own rain gauge to predict the exact minute rain begins, calculates true garden evapotranspiration (ET₀) to stop overwatering, protects awnings from wind gusts, and predicts storms offline — running 100% locally on your machine with zero cloud dependencies.
Precipitation nowcasting uses your own gauge as ground truth to give you a live countdown before the first drop falls.
Most weather stations in Home Assistant just show raw numbers. ws_core transforms those readings into automatic protection for your home and garden:
| Your Weather Station Today | With Weather Station Core |
|---|---|
Displays 21°C and 15 km/h wind on a card |
Auto-retracts awnings and blinds when dangerous wind gusts hit |
| Sprinklers run on a dumb timer regardless of weather | Skips watering using locally calculated evapotranspiration (ET₀) and rainfall |
| Cloud weather app says "40% chance of rain" | TTS voice alert: "🌧️ Rain starting in 7 minutes at your house — close the skylight" |
| Internet drops = weather forecasts vanish | 100% offline Zambretti forecast predicts the next 12 hours from local pressure trends |
| Raw sensors without context | 50+ core derived insights: frost point, heat stress (UTCI/WBGT), fire risk, wet-bulb |
Know before the first drop hits. Enable Precipitation Nowcast to combine local radar models with your physical rain gauge.
- Live countdown:
sensor.ws_minutes_until_raingives you minutes to close skylights, pull in outdoor cushions, or walk the dog. - Pre-rain notifications: Alert your family via phone or smart speaker before rain starts.
- Rain dry-time:
sensor.ws_minutes_until_drylets you know when outdoor surfaces will dry after a shower.
Stop running sprinklers after a downpour. ws_core implements scientific evapotranspiration formulas so your irrigation knows what the soil actually needs.
- Reference ET₀ (FAO-56 Penman-Monteith & Hargreaves-Samani): Calculates daily water loss based on solar radiation, temperature, humidity, and wind.
- Smart Irrigation bridge: Seamlessly feeds ET₀ data into the popular
HAsmartirrigationintegration. - One-click rain skip: Automatically cancel tomorrow's watering if today's rainfall exceeded lawn requirements.
Safeguard your home against high winds, freezing temperatures, and dangerous heat:
- High-wind awning & blind protection: Instant alerts and automatic retraction commands when wind gusts exceed structural limits.
- Freeze & frost warnings: Accurate Buck (1981) frost-point derivation alerts you to protect sensitive plants and outdoor water pipes.
- Heat stress monitoring (UTCI & WBGT): Gold-standard comfort indices used by the WHO to warn when outdoor work or sports become hazardous.
- Fire weather indices: Complete implementations of Canadian FWI, Australian McArthur FFDI, and US Fosberg FFWI.
Your smart home shouldn't stop working when your internet connection goes down.
- Offline Zambretti forecasting: A mathematical barometric forecast calibrated to your hemisphere and climate region — 100% local, no cloud, no API keys.
- Privacy by design: All 50+ core derived sensors are computed directly inside Home Assistant on your local hardware.
- Zero telemetry: No coordinates, sensor readings, or personal data ever leave your network unless you explicitly enable an optional external service.
If your weather station is already in Home Assistant, it works with ws_core.
| Station Brand | Supported Models / Integrations | What ws_core Uses |
|---|---|---|
| Ecowitt / Ambient Weather | GW-series, WS90, Wittboy, WH57 lightning, soil, and rain gauges | Outdoor temp, humidity, absolute pressure, wind, rain, lux/solar, lightning |
| WeatherFlow Tempest | Tempest Home Assistant integration & local UDP / MQTT | Air temp, station pressure, wind speed/gust, rain, UV, illuminance |
| Davis Instruments | WeatherLink IP, Vantage Pro2, Vantage Vue | Classic PWS measurements, rain year, bar absolute |
| Netatmo | Netatmo Smart Weather Station (Outdoor + Rain + Wind) | Outdoor module readings, rain gauge total, anemometer wind |
| Blitzortung (Free Fallback) | Blitzortung HA integration (crowdsourced network) | Auto-discovered fallback: strikes, distance, proximity (no hardware needed!) |
| Shelly / ESPHome / DIY | Any custom sensor entity with standard device classes | Temperature, humidity, pressure, wind, cumulative rain total |
👉 Need help mapping your entities? Check out our Hardware Mapping Guide.
Don't spend hours writing YAML. We provide ready-to-import blueprints with sensible defaults:
| Blueprint | What It Does | One-Click Install |
|---|---|---|
| Rain Start Warning | Announce via TTS or mobile notification when rain is imminent |  |
| Irrigation Rain Skip | Automatically skip watering when rainfall or ET₀ indicates sufficient moisture | |
| High Wind Protection | Automatically retract awnings and blinds when severe wind gusts are detected | |
| Freeze & Frost Protection | Alert before freezing and automatically shut off outdoor irrigation valves | |
| Heat Stress Alert | Notify when apparent temperature (UTCI) reaches dangerous levels for outdoor activity | |
👉 Browse all 10 blueprints and configuration options in the Blueprint Documentation.
- Open HACS in your Home Assistant sidebar.
- Click Integrations → ⋮ (top right) → Custom repositories.
- Paste
https://github.com/kmich/ha_ws_core, choose category Integration, and click Add. - Search for "Weather Station Core", download, and restart Home Assistant.
- In Home Assistant, go to Settings → Devices & Services → Add Integration.
- Search for "Weather Station Core".
- Auto-Discovery will automatically identify and suggest matching sensor entities from your station.
- Review the mapped entities, click Submit, and you're done!
50+ core sensors appear instantly. You can enable optional enrichments (air quality, nowcast, multi-network upload) at any time under Configure → Features.
ws_core includes pre-built, responsive Lovelace dashboards tailored for your weather data:
| Mobile View | Desktop View |
|---|---|
 |
 |
In the dashboards/ directory, you'll find:
- Vanilla Dashboard: Works immediately with 100% native Home Assistant cards (zero custom card dependencies).
- Enhanced Dashboard: Uses popular cards (
mushroom,mini-graph-card) with custom severity color bands and gauges.
Behind the friendly sensors, ws_core runs rigorous, peer-reviewed meteorological algorithms and advanced power packs:
- 🌧️ Nowcast Ground-Truth Blending: Merges high-resolution NWP radar grids with your physical rain gauge (70% local / 30% forecast) for pinpoint start times.
- 🌿 Plant Health & Agricultural Spraying: Computes Delta-T spray window suitability (know the exact window to spray fertilizer without evaporation or drift), VPD (Vapor Pressure Deficit) for greenhouses, and Leaf Wetness to detect fungal risks.
- ⚡ Energy & HVAC Load Optimization: Tracks Heating Degree Days (HDD) and Cooling Degree Days (CDD) to forecast heat pump and air conditioning demand and automate pre-cooling with solar energy.
- 🌍 10-Year Climate Normals (ERA5): Compares today's temperature and rain against a 10-year historical baseline for your exact coordinates (
sensor.ws_temp_anomaly_normal). - ❄️ Snow Accumulation & Phase: Uses wet-bulb temperature and precipitation rate to determine snow, sleet, or rain and estimate snow accumulation without requiring a heated snow gauge.
- 🎯 Native HA Event Entities: Fires instant sub-second event triggers (
event.ws_rain_event,event.ws_frost_event,event.ws_lightning_event) for lag-free automations without numeric polling. - 🌡️ Human Thermal Comfort (UTCI & WBGT): Full Bröde (2012) polynomial modeling human heat balance across radiation, humidity, and wind.
- 📡 8-Network Simultaneous Uplink: Broadcasts your station observations simultaneously to WUnderground, Windy, Weathercloud, PWSWeather, WOW, AWEKAS, CWOP, and OpenWeatherMap.
- 🌐 Full Translation Parity: Available in English, French, German, Spanish, Italian, Dutch, Polish, and Portuguese.
For complete equations, source citations, and mathematical references, see the Scientific Documentation.
ws_core is strictly local-first. All core sensors are derived locally. Optional third-party features are disabled by default and only contact external services when explicitly enabled:
| Feature | Destination | Data Sent | When Used |
|---|---|---|---|
| Core Derived Sensors | Local Machine | None (processed locally) | Always (Default) |
| Precipitation Nowcast & AQI | Open-Meteo API | Approximate Coordinates | Only if enabled |
| French Vigilance | Météo-France Public API | Department Code | Only if enabled |
| PWS Network Uploads | Selected Network (e.g. WU, WOW) | Station Readings & User Credentials | Only if enabled |
| MQTT Discovery | Local MQTT Broker | Derived Sensor Values | Only if enabled |
Diagnostics exports automatically redact all credentials and coordinates before download.
Why not just write a few template sensors in YAML?
Template sensors are great for simple math (e.g., Fahrenheit to Celsius), but they cannot easily compute complex meteorological models like Penman-Monteith ET₀, Bröde UTCI polynomials, or 90-day adaptive Brier scores. Template sensors also don't include blueprints, dashboards, diagnostics, or auto-discovery.Can I migrate from the Thermal Comfort integration?
Yes! `ws_core` provides a drop-in replacement with identical or higher-precision comfort indices. Follow our step-by-step Thermal Comfort Migration Guide to preserve entity history.Do I need any API keys?
No. The core integration and all 50+ base sensors require zero API keys and work completely offline. Optional extras like Open-Meteo precipitation nowcasting and air quality use free public APIs that also require no registration.What if some of my sensors are temporarily offline?
`ws_core` handles sensor degradation gracefully. If your wind sensor goes offline, wind-dependent metrics will reportunavailable, while independent metrics (like barometric pressure trends and temperature comfort) continue working seamlessly.
- 💬 Discussions & Showcase: Share your dashboards and station setups in GitHub Discussions.
- 🐛 Bug Reports & Feature Requests: Open an issue on GitHub Issues.
- 📖 Full Documentation: Visit the Weather Station Core Documentation.