Weather MCP Server

A Model Context Protocol (MCP) server that provides real-time weather alerts and forecasts using the National Weather Service (NWS) API. This server is built with Python and fastmcp, and is designed to integrate seamlessly with Claude Desktop.

Features

This server exposes two main tools:

get_alerts(state: str): Retrieves active weather alerts for a specific US state (e.g., "TX", "CA").
Returns a list of alerts including event type, severity, description, and instructions.
get_forecast(latitude: float, longitude: float): Fetches the weather forecast for a given location.
Automatically resolves the NWS grid point for the coordinates.
Returns a detailed forecast including temperature, wind speed, and detailed descriptions for upcoming periods.

Prerequisites

Docker (required)

Installation & Usage

1. Build the Docker Image

docker build -t weather-mcp .

2. Configure Claude Desktop

Add the following to your claude_desktop_config.json:

{
  "mcpServers": {
    "weather": {
      "command": "docker",
      "args": [
        "run",
        "-i",
        "--rm",
        "weather-mcp"
      ]
    }
  }
}

Development

To test your changes during development, rebuild and run the container manually:

# Rebuild the image
docker build -t weather-mcp .

# Run the container (interactive mode to test stdin/stdout)
docker run -i --rm weather-mcp

You can then paste JSON-RPC messages (if you know them) or simply ensure the container starts without errors.

To verify a specific tool execution (e.g., getting alerts), you can pipe a request into the container:

echo '{"jsonrpc": "2.0", "id": 1, "method": "tools/call", "params": {"name": "get_alerts", "arguments": {"state": "TX"}}}' | docker run -i --rm weather-mcp

Technologies

mcp: The official Python SDK for the Model Context Protocol.
httpx: A next-generation HTTP client for Python.
uv: An extremely fast Python package installer and resolver.

Weather MCP Server