avalanche-org-mcp-server

A minimal Model Context Protocol (MCP) server that wraps the Avalanche.org Public API map-layer endpoints. It lets LLMs look up avalanche danger ratings by location, retrieve raw forecast GeoJSON, and query historic conditions.

Features

• Danger lookup by lat/lon — find the avalanche zone for any point and get its current danger rating
• Historic danger lookup — same as above, but for a specific past date
• Raw map-layer GeoJSON — full FeatureCollection for all avalanche centers, or scoped to one center

Data sourced from the Avalanche.org Public API. See the API docs for details.

Quick Start

Claude Desktop (npx — recommended)

Add this to your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json on macOS):

{
  "mcpServers": {
    "avalanche-org": {
      "command": "npx",
      "args": ["-y", "avalanche-org-mcp-server"]
    }
  }
}

No install required. Claude will download and run it automatically.

Global npm install

npm install -g avalanche-org-mcp-server

{
  "mcpServers": {
    "avalanche-org": {
      "command": "avalanche-org-mcp-server"
    }
  }
}

Docker

docker pull ghcr.io/haydenwade/avalanche-org-mcp-server:latest

{
  "mcpServers": {
    "avalanche-org": {
      "command": "docker",
      "args": ["run", "--rm", "-i", "ghcr.io/haydenwade/avalanche-org-mcp-server:latest"]
    }
  }
}

From source

git clone https://github.com/haydenwade/avalanche-org-mcp-server.git
cd avalanche-org-mcp-server
npm install
npm run build

{
  "mcpServers": {
    "avalanche-org": {
      "command": "node",
      "args": ["/absolute/path/to/avalanche-org-mcp-server/dist/src/index.js"]
    }
  }
}

Tools

avalanche_danger_rating_by_point

Get the current avalanche danger rating for a lat/lon point. Returns the zone the point falls in, or the nearest zone if preferNearest is true.

Parameter	Type	Required	Description
lat	number	yes	Latitude in decimal degrees
lon	number	yes	Longitude in decimal degrees
preferNearest	boolean	no	Fall back to nearest zone if point is outside all polygons (default: true)
centerId	string	no	Scope search to a specific avalanche center (e.g. "UAC", "CBAC")

Example input:

{ "lat": 40.5763, "lon": -111.7522, "preferNearest": true, "centerId": "UAC" }

<details> <summary><strong>Example output</strong></summary>

{
  "match": "inside_zone",
  "distance_km": 0,
  "distance_miles": 0,
  "zone": {
    "id": "zone-1",
    "name": "Salt Lake",
    "state": "UT"
  },
  "center": {
    "id": "UAC",
    "name": "Utah Avalanche Center",
    "timezone": "America/Denver",
    "link": "https://utahavalanchecenter.org"
  },
  "danger": {
    "level": 3,
    "label": "Considerable",
    "color": "#f1a302"
  },
  "travel_advice": "Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.",
  "forecast_url": "https://utahavalanchecenter.org/forecast/salt-lake",
  "validity": {
    "start_date": "2026-03-22",
    "end_date": "2026-03-23"
  },
  "warning": null
}

</details>

---

historic_avalanche_danger_rating_by_point

Same as above, but for a specific historic date. Returns all the same fields plus day.

Parameter	Type	Required	Description
lat	number	yes	Latitude in decimal degrees
lon	number	yes	Longitude in decimal degrees
day	string	yes	Date in YYYY-MM-DD format
preferNearest	boolean	no	Fall back to nearest zone (default: true)
centerId	string	no	Scope to an avalanche center

Example input:

{ "lat": 40.5763, "lon": -111.7522, "day": "2025-02-24", "preferNearest": true }

<details> <summary><strong>Example output</strong></summary>

{
  "match": "inside_zone",
  "distance_km": 0,
  "distance_miles": 0,
  "zone": { "id": "zone-1", "name": "Salt Lake", "state": "UT" },
  "center": { "id": "UAC", "name": "Utah Avalanche Center", "..." : "..." },
  "danger": { "level": 3, "label": "Considerable", "color": "#f1a302" },
  "travel_advice": "Dangerous avalanche conditions. ...",
  "forecast_url": "https://utahavalanchecenter.org/forecast/salt-lake",
  "validity": { "start_date": "2025-02-24", "end_date": "2025-02-25" },
  "warning": null,
  "day": "2025-02-24"
}

</details>

---

raw_map_layer

Returns the raw Avalanche.org map-layer GeoJSON FeatureCollection for all avalanche centers.

Parameter	Type	Required	Description
day	string	no	Historic date in YYYY-MM-DD format

<details> <summary><strong>Example output</strong></summary>

{
  "geojson": {
    "type": "FeatureCollection",
    "features": [ "... full GeoJSON features ..." ]
  }
}

</details>

---

raw_map_layer_by_avalanche_center

Returns the raw map-layer GeoJSON FeatureCollection for a single avalanche center.

Parameter	Type	Required	Description
centerId	string	yes	Avalanche center ID (e.g. "CBAC", "NWAC", "UAC")
day	string	no	Historic date in YYYY-MM-DD format

<details> <summary><strong>Example output</strong></summary>

{
  "geojson": {
    "type": "FeatureCollection",
    "features": [ "... full GeoJSON features ..." ]
  }
}

</details>

Development

Requires Node.js >= 18.

npm install
npm run build
npm test

To interactively test tools with the MCP Inspector:

npx @modelcontextprotocol/inspector node dist/src/index.js

Project structure

src/
  index.ts          # Entry point — server setup + stdio transport
  tools.ts          # Tool registration
  constants.ts      # API URLs and timeouts
  types.ts          # GeoJSON type definitions
  api/
    mapLayer.ts     # Map-layer fetch + GeoJSON normalization
  lib/
    geometry.ts     # Point-in-polygon, haversine distance, bounds
    dangerLookup.ts # Danger rating lookup logic
    validation.ts   # Date and coordinate validation
test/
  *.test.ts         # Tests (node:test)

Contributing

1. Fork the repo
2. Create a feature branch (git checkout -b my-feature)
3. Make your changes and add tests
4. Run npm test to make sure everything passes
5. Open a pull request

License

MIT