Nws

What the Nws MCP server does

The Nws MCP server exposes selected data from the US National Weather Service through the Model Context Protocol. It is intended for agents that need current US weather information without managing an API key. The underlying source is api.weather.gov, which provides public forecast, alert, and observation data.

The server supports geographic forecasts, active hazard information, and station-based conditions. Location-oriented tools accept latitude and longitude, while observations use an ICAO station identifier. Coverage is limited to the United States.

How it works

You can connect an MCP client to the hosted Pipeworx endpoint at https://gateway.pipeworx.io/nws/mcp. That endpoint lists the Nws tools along with shared Pipeworx gateway tools, including routing and discovery functions. The gateway can also be used through its full endpoint at https://gateway.pipeworx.io/mcp; the pack endpoint determines which tools are listed directly, while gateway routing can reach other catalog sources.

For a local connection, run @pipeworx/mcp-nws with npx. The local process communicates through stdin and stdout and exposes only the weather tools, without the gateway's shared meta-tools. Direct HTTP callers can invoke a tool through the gateway's /v1/tools/ endpoints.

Setup and configuration

A hosted MCP connection can be added with the URL below:

{
  "mcpServers": {
    "nws": {
      "url": "https://gateway.pipeworx.io/nws/mcp"
    }
  }
}

For local stdio use, configure the client to run:

{
  "mcpServers": {
    "nws": {
      "command": "npx",
      "args": ["-y", "@pipeworx/mcp-nws"]
    }
  }
}

No account or API key is required for the initial gateway calls, and the standalone package does not require a Pipeworx account. The upstream NWS API requires a unique User-Agent header; this package sends Pipeworx-NWS-MCP/0.1 (contact@mojibake.ai) for its requests.

Tools and capabilities

The Nws MCP server provides these pack-specific tools:

• get_forecast(latitude, longitude) returns a seven-day text forecast for a US coordinate.
• get_hourly_forecast(latitude, longitude, max_hours?) returns hourly forecast data, with an optional hour limit.
• get_alerts(area?, latitude?, longitude?, severity?, urgency?, event?, limit?) retrieves active watches, warnings, and advisories using optional filters.
• get_observation(station_id) returns the latest observation from an ICAO weather station.

Agents can call these tools directly or use the gateway's ask_pipeworx function to ask a plain-language question and let the gateway select and populate a tool call.

Limitations and notes

The Nws MCP server is restricted to US locations and NWS data. It does not provide a general global weather service. Hosted pack connections include shared gateway tool schemas, so the number of listed tools is larger than the four pack-specific tools. The local stdio mode avoids those additional schemas but does not provide gateway-wide routing. The gateway also offers direct HTTP inspection and invocation endpoints for clients that do not support MCP.