Weather MCP Server

A Model Context Protocol (MCP) server that provides weather alerts and forecasts using the National Weather Service (NWS) API.

Features

• Weather Alerts: Get active weather alerts for any US state

• Location Forecasts: Retrieve detailed weather forecasts for specific coordinates

• Real-time Data: Pulls live data from the official NWS API

• MCP Compliance: Fully compatible with Claude Desktop and other MCP clients

Installation

1. Clone the repository:

git clone https://github.com/MikeySharma/weather-mcp-server.git
cd weather-mcp-server

2. Install dependencies:

npm install

3. Build the project:

npm run build

Configuration

Claude Desktop Setup

Add the following to your Claude Desktop MCP settings:

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
Windows: %APPDATA%/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "weather": {
      "command": "node",
      "args": ["/absolute/path/to/weather-mcp-server/build/index.js"],
      "env": {
        "NODE_ENV": "production"
      }
    }
  }
}

Environment Variables

The server uses the following environment variables (optional):

# For debugging
export DEBUG_MCP=true
export NODE_ENV=development

Usage

Available Tools

1. Get Weather Alerts

get_alerts(state: string)

• state: Two-letter US state code (e.g., "CA", "NY", "TX")

• Returns: Active weather alerts for the specified state

2. Get Weather Forecast

get_forecast(latitude: number, longitude: number)

• latitude: Geographic latitude (-90 to 90)

• longitude: Geographic longitude (-180 to 180)

• Returns: 7-day weather forecast for the location

Example Usage with Claude

@weather get_alerts(state: "CA")

@weather get_forecast(latitude: 37.7749, longitude: -122.4194)

API Reference

National Weather Service API

This server uses the official NWS API:

• Base URL: https://api.weather.gov

• Rate Limits: Please respect rate limits (typically 10 requests/minute)

• Data Coverage: US territories only

Response Formats

Alerts Response

{
  features: Array<{
    properties: {
      event: string;
      severity: string;
      description: string;
      instruction: string;
      areaDesc: string;
      effective: string;
      expires: string;
    }
  }>
}

Forecast Response

{
  properties: {
    periods: Array<{
      name: string;
      temperature: number;
      temperatureUnit: string;
      windSpeed: string;
      windDirection: string;
      shortForecast: string;
      detailedForecast: string;
    }>
  }
}

Development

Project Structure

weather-mcp-server/
├── src/
│   ├── index.ts          # Main server entry point
│   ├── tools/
│   │   └── weather-tools.ts  # Tool implementations
│   └── helpers/
│       └── weather-service.helpers.ts  # API helpers
├── build/                # Compiled JavaScript
├── package.json
└── tsconfig.json

Building from Source

1. Install TypeScript (if not already installed):

npm install -g typescript

2. Build the project:

npm run build

3. Development mode with watch:

npm run dev

Testing

Run the server in standalone mode for testing:

npm start

Error Handling

The server includes comprehensive error handling for:

• Network timeouts

• API rate limiting

• Invalid coordinates

• Unsupported locations (non-US)

• Malformed responses

Limitations

• US Only: NWS API only provides data for US territories

• Rate Limits: Respect NWS API rate limits (10 requests/minute)

• Coordinate Precision: Limited to 4 decimal places for grid points

Contributing

1. Fork the repository

2. Create a feature branch (git checkout -b feature/amazing-feature)

3. Commit your changes (git commit -m 'Add amazing feature')

4. Push to the branch (git push origin feature/amazing-feature)

5. Open a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

• National Weather Service for providing the free API

• Anthropic for the Model Context Protocol specification

• MCP SDK developers

Support

For issues and questions:

1. Check the existing issues

2. Create a new issue with detailed description

3. Include error logs and reproduction steps

Changelog

v1.0.0

• Initial release with alerts and forecast functionality

• MCP protocol compliance

• TypeScript implementation

• Comprehensive error handling

Note: This server requires an internet connection to fetch weather data from the NWS API.