OpenWeather MCP Server

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A simple weather forecast MCP (Model Control Protocol) server providing global weather forecasts and current weather conditions.

Screenshot of Claude Desktop using the MCP Weather Service

Features

• No separate configuration file needed; API key can be passed directly through environment variables or parameters
• Support for querying weather conditions anywhere in the world
• Provides current weather and future forecasts
• Detailed weather information including temperature, humidity, wind speed, etc.
• Support for different time zones

Installation Requirements

pip install mcp-server requests pydantic

Usage

1. Get an OpenWeatherMap API Key

Visit OpenWeatherMap and register an account to obtain an API key.

2. Run the Server

There are two ways to provide the API key:

Method 1: Using Environment Variables

# Set environment variables
export OPENWEATHER_API_KEY="your_api_key"  # Linux/Mac
set OPENWEATHER_API_KEY=your_api_key  # Windows

# Run the server
python weather_mcp_server.py

Method 2: Provide When Calling the Tool

Run directly without setting environment variables:

python weather_mcp_server.py

When calling the tool, you'll need to provide the `api_key` parameter.

3. Use in MCP Client Configuration

Add the following configuration to your MCP-supported client:

{
  "weather_forecast": {
    "command": "python",
    "args": [
      "/full_path/weather_mcp_server.py"
    ],
    "env": {
      "OPENWEATHER_API_KEY": "your_openweathermap_key_here"
    },
    "disabled": false,
    "autoApprove": ["get_weather", "get_current_weather"]
  }
}

4. Available Tools

get_weather

Get current weather and forecast for a specified location.

Parameters:

• `location`: Location name, e.g., "Beijing", "New York", "Tokyo"
• `api_key`: OpenWeatherMap API key (optional, will read from environment variable if not provided)
• `timezone_offset`: Timezone offset in hours, e.g., 8 for Beijing, -4 for New York. Default is 0 (UTC time)

get_current_weather

Get current weather for a specified location.

Parameters:

• `location`: Location name, e.g., "Beijing", "New York", "Tokyo"
• `api_key`: OpenWeatherMap API key (optional, will read from environment variable if not provided)
• `timezone_offset`: Timezone offset in hours, e.g., 8 for Beijing, -4 for New York. Default is 0 (UTC time)

Usage Example

AI assistant call example:

User: What's the weather like in New York right now?

AI: Let me check the current weather in New York for you.
[Calling get_current_weather("New York", timezone_offset=-4)]

Current weather in New York: 18°C, partly cloudy, humidity 65%, wind speed 3.5m/s.

Troubleshooting

If you encounter a "No API key provided" error, make sure:

1. You have set the OPENWEATHER_API_KEY in environment variables, or

2. You are providing the api_key parameter when calling the tools

If the location name is incorrect, you might receive a "Location not found" error. Try using a more accurate city name or add a country code, e.g., "Beijing,CN" or "Paris,FR".