OpenWeather

What is mcp-openweather?

mcp-openweather is a simple MCP (Mycroft Core Protocol) service written in Go that integrates with the free OpenWeatherMap API. It allows users to retrieve current weather conditions and a 5-day weather forecast for a specified location.

How to use mcp-openweather?

To use mcp-openweather, you need Go 1.20+ and an OpenWeatherMap API key. After cloning the repository and building the executable, you must set the OWM_API_KEY environment variable with your API key. The service can then be run as an MCP server. For integration with Claude Desktop, you can use Smithery for automatic installation. To query the weather, you send an MCP request with the tool set to "weather" and params including the city (required), and optional units (c, f, or k) and lang (e.g., en, de, fr).

Key Features of mcp-openweather

Current Weather Conditions: Provides real-time weather data.
5-Day Weather Forecast: Offers a forecast for the next five days.
Configurable Units: Supports Celsius, Fahrenheit, and Kelvin.
Multi-language Support: Allows weather information to be retrieved in various languages.
Simple MCP Integration: Designed for easy integration into MCP environments.

Use Cases of mcp-openweather

Smart Home Systems: Integrate weather information into home automation routines.
Personal Assistants: Provide weather updates through voice commands or automated responses.
Custom Applications: Develop applications that require weather data for specific locations.
Data Analysis: Collect weather data for analysis and visualization.

FAQ from mcp-openweather

Missing API key: Ensure the OWM_API_KEY environment variable is set.
Invalid city: The service will return an error if the specified city is not found.
Network issues: Connectivity problems can lead to errors when fetching weather data.

MCP Weather Service

A simple MCP service that provides current weather and 5-day forecast using the free OpenWeatherMap API.

Features

Current weather conditions
5-day weather forecast
Configurable units (Celsius/Fahrenheit/Kelvin)
Multi-language support
Simple MCP integration

Prerequisites

Go 1.20+
OpenWeatherMap API key

Installation

Get OpenWeatherMap API key from https://openweathermap.org/api

Clone repository:

git clone https://github.com/mschneider82/mcp-openweather.git
cd mcp-openweather

Build:
```
go build -o mcp-weather
```

Installing via Smithery

To install MCP Weather Service for Claude Desktop automatically via Smithery:

npx -y @smithery/cli install @mschneider82/mcp-openweather --client claude

Configuration

Set required environment variable:

export OWM_API_KEY="your_api_key_here"

Usage


 "mcpServers": {
     "mcp-openweather": {
         "command": "/home/YOURUSER/git/mcp-openweather/mcp-openweather",
         "env": {
             "OWM_API_KEY": "PUT_API_KEY_HERE"
         }
     }
 }

MCP Parameters

 {
     "tool": "weather",
     "params": {
         "city": "Berlin",          // Required
         "units": "c",             // Optional (c|f|k)
         "lang": "en"              // Optional (en|de|fr|...)
     }
 }

Example Response

 Current weather for München:
     Conditions:  Klarer Himmel 
     Now:         17.78 metric
     High:        18.66 metric
     Low:         17.36 metric
     Pressure:    1017
     Humidity:    40
     FeelsLike:   16.66
     Wind Speed:  1.79
     Wind Degree:    61
     Sunrise:     1747107429 Unixtime
     Sunset:      1747161784 Unixtime
 Weather Forecast for München:
 Date & Time: 2025-05-13 12:00:00 +0000 UTC
 Conditions:  Clear Klarer Himmel
 Temp:        17.78 
 High:        18.93 
 Low:         17.78

 Date & Time: 2025-05-13 15:00:00 +0000 UTC
 Conditions:  Clear Klarer Himmel
 Temp:        18.33 
 High:        19.44 
 Low:         18.33

 Date & Time: 2025-05-13 18:00:00 +0000 UTC
 Conditions:  Clear Klarer Himmel
 Temp:        16.32 
 High:        16.32 
 Low:         15.59

 Date & Time: 2025-05-13 21:00:00 +0000 UTC
 Conditions:  Clear Klarer Himmel
 Temp:        9.18 
 High:        9.18 
 Low:         9.18
...

Error Handling

Common error scenarios:

Missing API key: FATAL: OWM_API_KEY environment variable not set

Invalid city: current weather error: failed to fetch current weather: city not found

Network issues: failed to fetch forecast: context deadline exceeded

Development

Contributions welcome! Please follow these steps:

Fork the repository

Create a feature branch

Commit changes

Push to the branch

Create a Pull Request

License

MIT License - see LICENSE for details

OpenWeather Overview