arjones/weather-mcp

Weather MCP Server

A Model Context Protocol (MCP) server that provides weather data using the National Weather Service (NWS) API. Source MCP / For Server Developers / Quickstart

Features

• Weather Alerts: Get active weather alerts for any US state
• Weather Forecast: Get detailed weather forecasts for specific coordinates
• US Coverage: Full coverage of United States territories

Project Structure

src/
├── index.ts      # MCP server configuration and main entry point
├── types.ts      # TypeScript interfaces and type definitions
├── api.ts        # NWS API client and request handling
└── forecast.ts   # Business logic for alerts and forecast processing

Architecture Overview

• index.ts: MCP server setup, tool registrations, and main function
• types.ts: All TypeScript interfaces (AlertFeature, ForecastPeriod, etc.)
• api.ts: HTTP client for NWS API with error handling
• forecast.ts: Core business logic for formatting and processing weather data

Setup

1. Install dependencies:

   npm install
   

2. Build the project:

   npm run build
   

Available Tools

get_alerts

Get weather alerts for a US state.

Parameters:

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

Example:

{
  "state": "CA"
}

get_forecast

Get weather forecast for specific coordinates.

Parameters:

• latitude (number): Latitude (-90 to 90)
• longitude (number): Longitude (-180 to 180)

Example:

{
  "latitude": 37.7749,
  "longitude": -122.4194
}

Debugging with MCP Inspector

The MCP Inspector is a powerful tool for debugging and testing MCP servers.

Installation

Use it directly with npx:

npx @modelcontextprotocol/inspector node build/index.js

Usage

Connect to your server:

• Server type: stdio
• Command: node
• Arguments: build/index.js
• Click Connect