signalk-weather-map

A SignalK webapp that displays meteorological forecast data on an interactive MapLibre globe — wind barbs, temperature, sea-surface temperature, cloudiness, precipitation, pressure and gusts, powered by any SignalK weather provider.

Features

• Wind barbs — standard meteorological notation (½ bar = 5 kt, bar = 10 kt, pennant = 50 kt)
• Gusts — same barb display based on gust speed
• Temperature — colour-coded cells with numeric label (blue → green → yellow → red)
• Sea-surface temperature — dedicated −2 to 35 °C colour scale with numeric labels
• Cloudiness — transparency-based grey overlay (0 % = transparent, 100 % = dark grey)
• Precipitation — colour-coded intensity (transparent → light blue → blue → purple → red)
• Pressure — colour-coded cells with numeric hPa label (dark blue = storm/low < 960 → cyan → green ≈ 1013 → orange → dark red = anticyclone > 1022)
• 3D globe — MapLibre globe projection keeps weather patterns legible at high latitudes
• Automatic grid density — stable spacing adapts to zoom level (~36 px between points)
• Forecast time slider — browse all steps, or play them in a continuous loop
• Multi-provider support — select any registered SignalK weather provider; inspect its coverage, steps and layers, and set it as default from its information panel
• Responsive control dock — fixed two-row dock, full timeline and independently hideable legend
• Vessel position — boat marker oriented to true heading (falls back to north if unavailable)
• Client-side cache — 30-minute localStorage + memory cache; parallel batch fetching (15 concurrent)
• i18n — UI language detected from the browser (French and English supported)

Requirements

• SignalK server with at least one weather provider plugin installed and enabled
  (e.g. signalk-grib-weather-provider, Open-Meteo, etc.)
• Node.js ≥ 18
• A browser with WebGL2 and hardware acceleration enabled

Installation

From npm (recommended)

In the SignalK server's app store, search for signalk-weather-map and install it.

Or from the command line inside the SignalK data directory:

npm install signalk-weather-map

Then restart the SignalK server.

Manual / development

cd ~/.signalk/   # or your SignalK data directory
mkdir -p local-plugins
git clone https://github.com/macjl/signalk-weather-map local-plugins/signalk-weather-map
# Add to package.json dependencies:
#   "signalk-weather-map": "file:./local-plugins/signalk-weather-map"
npm install

Usage

Once installed, the webapp is available at:

http://<signalk-host>:<port>/signalk-weather-map/

Or open it from the SignalK dashboard → Webapps.

Layer selector

| Layer | Description | |---|---| | Wind | Barbs based on true wind speed | | Gusts | Barbs based on gust speed | | Temperature | Colour-coded cell fill with °C label | | Water | Sea-surface temperature colour fill with °C label | | Cloudiness | Grey transparency proportional to cloud cover | | Precipitation | Colour intensity proportional to rain volume | | Pressure | Colour-coded cell fill with hPa label (blue = low, red = high) |

Tooltip

Hover over any cell to see full data: wind speed & direction, gusts, temperature, MSLP, humidity, cloud cover and precipitation.

Provider selector

If multiple weather providers are registered, select one from the Source dropdown. Use the i button to inspect coverage, forecast steps and layers, or to make it the server-wide default.

Weather API

This plugin uses the standard SignalK v2 Weather API:

GET /signalk/v2/api/weather/forecasts/point?lat=&lon=&provider=<pluginId>
GET /signalk/v2/api/weather/_providers
POST /signalk/v2/api/weather/_providers/_default/:id

Any provider that implements this API is compatible.

Development

git clone https://github.com/macjl/signalk-weather-map
cd signalk-weather-map
# Edit public/index.html — no build step required (vanilla JS + MapLibre CDN)

License

MIT © Jean-Laurent Girod