Weather MCP Server

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

Features

• Weather Alerts — Retrieve active NWS weather alerts for any US state
• Weather Forecast — Get a detailed forecast for any US location by latitude/longitude
• Weather Briefing Prompt — A pre-built prompt that combines alerts and forecast into a comprehensive briefing

Prerequisites

• Node.js v18 or later
• An MCP-compatible client (e.g. Claude Desktop)

Note: The NWS API only supports locations within the United States.

Installation

npm install
npm run build

Usage

Run the server directly via stdio (the standard MCP transport):

node build/index.js

Or use the weather bin alias after a global/local install:

npx weather

Integrating with Claude Desktop

Add the following to your claude_desktop_config.json:

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

Tools

get_alerts

Retrieves active weather alerts for a US state.

Parameter	Type	Description
state	string	Two-letter state code (e.g. CA, NY)

get_forecast

Retrieves the weather forecast for a specific US location.

Parameter	Type	Description
latitude	number	Latitude of the location (-90–90)
longitude	number	Longitude of the location (-180–180)

Prompts

weather-briefing

Generates a comprehensive weather briefing for a US state.

Argument	Type	Description
state	string	Two-letter US state code (e.g. CA, NY)
latitude	string	Latitude of a location within the state for the forecast
longitude	string	Longitude of a location within the state for the forecast

Development

# Build TypeScript
npm run build

# Source files
src/index.ts    # MCP server, tools, and prompts
src/helpers.ts  # NWS API client and shared types

License

ISC