MeteoSwiss MCP Server

🌦️ MeteoSwiss MCP Server

MCP server for MeteoSwiss weather data — powered by MeteoSwiss Open Data, the same data behind the MeteoSwiss app and website.

This package is the server half of the repo's skill vs. MCP case study — the same data is also available as a no-infrastructure agent skill.

meteoswiss-mcp.ars.is — try it now, no setup needed.

• Multi-day forecasts for ~6000 Swiss locations (postal codes, stations, place names)
• Real-time measurements from ~300 stations (~160 full weather + ~140 precipitation-only), updated every 10 minutes
• Station discovery by name, canton, or GPS coordinates
• Pollen monitoring from ~15 stations across Switzerland
• Climate series from the National Basic Climatic Network (NBCN), going back decades
• MeteoSwiss website search and content retrieval

Use the Hosted Service

No installation required — the server is hosted at https://meteoswiss-mcp.ars.is.

Claude Code

claude mcp add meteoswiss https://meteoswiss-mcp.ars.is/mcp

Claude Desktop

Add to your configuration file (~/Library/Application Support/Claude/claude_desktop_config.json on macOS):

{
  "mcpServers": {
    "meteoswiss": {
      "command": "npx",
      "args": ["mcp-remote", "https://meteoswiss-mcp.ars.is/mcp"]
    }
  }
}

Cursor

Install from the Cursor Directory, or add manually via Settings → MCP → Add Server → paste https://meteoswiss-mcp.ars.is/mcp.

Claude.ai

Go to Settings → Integrations → Add MCP Server → paste https://meteoswiss-mcp.ars.is/mcp.

Example Questions

• "What's the weather forecast for Zurich this week?"
• "Wie wird das Wetter in Bern morgen?"
• "Quelle est la météo à Genève?"
• "Che tempo fa a Lugano?"
• "How windy is it at Jungfraujoch right now?"
• "Show me pollen data for Zurich"

Available Tools

Tool	Description
meteoswissLocalForecast	Multi-day forecasts for any Swiss location by postal code, station, or place name
meteoswissCurrentWeather	Real-time measurements from automatic weather stations (temperature, wind, humidity, pressure)
meteoswissStations	Search and browse the MeteoSwiss station network by name, canton, or coordinates
meteoswissPollenData	Current pollen concentration data from monitoring stations
meteoswissClimateData	NBCN climate series — temperature, precipitation, sunshine, and climate indicators going back decades
search	Search MeteoSwiss website content (DE, FR, IT, EN)
fetch	Fetch full content from MeteoSwiss pages in markdown, text, or HTML

Prompts

Pre-configured prompts for common weather queries:

Prompt	Language	Description
wetterNordschweiz	German	Forecast and current weather for Northern Switzerland
wetterSchweiz	German	Weather for any Swiss location
meteoSuisseRomande	French	Forecast and current weather for Western Switzerland
meteoTicino	Italian	Forecast and current weather for Southern Switzerland

---

Self-Hosting

Docker

docker run -p 3000:3000 ghcr.io/eins78/meteoswiss-mcp:latest

With custom URL:

docker run -p 3000:3000 -e PUBLIC_URL=https://your-domain.com ghcr.io/eins78/meteoswiss-mcp:latest

Docker Compose

docker compose up

From Source

git clone https://github.com/eins78/meteoswiss-llm-tools.git
cd meteoswiss-llm-tools/packages/meteoswiss-mcp
pnpm install
pnpm build
pnpm start

The server will be available at http://localhost:3000. MCP endpoint: http://localhost:3000/mcp.

Local MCP Configuration

{
  "mcpServers": {
    "meteoswiss-local": {
      "command": "npx",
      "args": ["mcp-remote", "http://localhost:3000/mcp"]
    }
  }
}

Environment Variables

Variable	Default	Description
PORT	3000	Server port
PUBLIC_URL	—	Full public URL for URL generation (e.g. https://meteoswiss-mcp.ars.is)
USE_TEST_FIXTURES	false	Use local test data instead of live API
BIND_ADDRESS	0.0.0.0	Interface to bind to
MAX_SESSIONS	100	Maximum concurrent sessions
MAX_SESSIONS_PER_CLIENT	10	Maximum concurrent sessions per client IP (as seen through TRUST_PROXY); further initialize requests get 429
SESSION_TIMEOUT_MS	300000	Session timeout in milliseconds
TRUST_PROXY	0	Number of reverse-proxy hops to trust for the client IP (X-Forwarded-For). Set 1 behind one proxy such as Caddy; leave 0 when clients reach the server directly, or they can spoof their IP past the rate limit
DEBUG	—	Debug namespaces (e.g. mcp:*)

---

Development

Prerequisites

• Node.js v22+ (nvm recommended)
• pnpm

Setup

nvm use
pnpm install

Commands

Command	Description
pnpm dev	Start with hot reloading
pnpm start	Start the server
pnpm build	Build TypeScript
pnpm test	Run tests
pnpm run lint	Type checking + ESLint
pnpm run fix	Auto-fix lint errors
pnpm run ci	Full CI (lint + build + test)
pnpm run dev:inspect	Test with MCP Inspector

Project Structure

src/
  index.ts              # Entry point
  server.ts             # MCP server (factory pattern)
  data/                 # Data access and transformation
  schemas/              # Zod schemas for validation
  tools/                # MCP tool implementations
  support/              # Logging, validation, HTTP, sessions
  views/homepage/       # Server homepage content
test/
  integration/          # Integration tests for all tools
  __fixtures__/         # Test data

Debugging

Enable debug output with the DEBUG environment variable:

DEBUG=mcp:* pnpm dev          # All debug output
DEBUG=mcp:tools pnpm dev      # Tool execution only
DEBUG=mcp:transport pnpm dev  # Transport layer only

See docs/debugging-guide.md for more.

Contributing

Contributions are welcome! Run pnpm run fix && pnpm run ci before committing.

See docs/releasing.md for the release process.

License

CC0-1.0 — public domain