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

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

2. Clone repository:

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

3. 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