Leopaexd/smhi-mcp

SMHI Weather Forecast MCP Server

An MCP (Model Context Protocol) server that provides weather forecasts from SMHI (Sveriges Meteorologiska och Hydrologiska Institut) for daily planning in Sweden.

Overview

This server integrates Swedish weather forecasts directly into your AI assistant workflow, providing real-time weather data with Stockholm local time and human-readable weather descriptions.

Features

• ✅ Structured data output - All weather parameters preserved in typed Pydantic models
• ✅ Human-readable text - Formatted markdown with emoji indicators
• ✅ Stockholm local time - All timestamps in CEST/CET (no UTC confusion!)
• ✅ Weather symbol meanings - Human-readable descriptions for all 27 SMHI weather symbols
• ✅ No information loss - 14 parameters per hour including weather symbol meanings
• ✅ Daytime focus - By default shows only waking hours (08:00-23:59) for practical planning
• ✅ Optional nighttime - Include night hours when needed or use "full" detail level
• ✅ Flexible detail levels - Choose between summary, detailed, or full output
• ✅ Planning-focused tips based on weather conditions

Installation

Using uv (recommended)

uv pip install fastmcp httpx pydantic loguru

Using pip

pip install fastmcp httpx pydantic loguru

Configuration

Add to your MCP settings (e.g., .cursor/mcp.json for Cursor):

{
  "mcpServers": {
    "smhi_weather": {
      "command": "uv",
      "args": ["run", "python", "path/to/smhi_weather_mcp/server.py"],
      "enabled": true
    }
  }
}

Or run directly:

python server.py

Usage

The server provides a single tool: get_weather_forecast

Parameters

• lat (float): Latitude (55.0-70.0, default: 59.32 for Stockholm/Södermalm)
• lon (float): Longitude (10.0-25.0, default: 18.04 for Stockholm/Södermalm)
• forecast_hours (int): Hours to forecast (1-120, default: 24)
• detail_level (str): Detail level for formatted text output
  • "summary": Just summary stats and planning tips
  • "detailed": Summary + daytime hours every 3 hours (default, 08:00-23:59)
  • "full": Summary + all hours including nighttime + extra details
• include_night (bool): Include nighttime hours (00:00-07:59) in output (default: False)

Example Queries

• "What's the weather like today? Should I bike to work?"
• "Check the weather forecast for planning my day"
• "Will it rain this afternoon during my planned break?"
• "What should I wear today based on the weather?"

Example Output

# 🌤️ Weather Forecast for Planning

**Current time:** 2025-10-05 09:15
**Location:** Lat 59.32, Lon 18.04
**Forecast updated:** 2025-10-05 08:00
**Showing:** Next 24 hours

## Today's Summary
- **Temperature range:** 8.5°C to 14.2°C
- **Precipitation:** Rain
- **Wind:** 4.2 m/s average, up to 6.8 m/s (gusts: 9.1 m/s)

## Detailed Forecast
**09:00** - 10.2°C, Rain (0.8 mm/h), Wind 4.5 m/s (gusts 7.2)
**12:00** - 12.8°C, Rain (1.2 mm/h), Wind 5.2 m/s (gusts 8.1)
**15:00** - 13.5°C, Drizzle, Wind 6.1 m/s
**18:00** - 11.0°C, Wind 4.8 m/s

## Planning Tips
- 🧥 Cold temperatures - bring warm layers
- ☔ Rain expected - bring umbrella, consider indoor activities

Data Structure

The tool returns a WeatherForecast object with:

• Structured data: Complete hourly forecasts with 14 parameters per hour
• Summary statistics: Min/max temp, wind, precipitation types
• Planning tips: Actionable advice based on conditions
• Formatted text: Human-readable markdown output

Each hourly forecast includes:

• Temperature, wind (speed/direction/gusts)
• Precipitation (type/amount)
• Humidity, visibility, pressure
• Cloud cover, thunder probability
• Weather symbol and its meaning

Weather Symbols

SMHI provides 27 weather symbols automatically decoded to human-readable descriptions:

API Information

• Data source: SMHI PMP3G API
• License: Creative Commons Attribution 4.0
• Rate limits: None specified for open data
• Documentation: https://opendata.smhi.se/apidocs/
• Coverage: Sweden (lat: 55-70°, lon: 10-25°)

Use Cases

🚴 Commute Planning

• Check if rain or snow is expected
• Wind conditions for biking
• Temperature for choosing clothing

🌳 Break Planning

• Best times for outdoor breaks
• When to avoid going outside
• Temperature considerations

📅 Activity Scheduling

• Reschedule outdoor meetings if bad weather expected
• Plan indoor vs outdoor tasks
• Adjust timing for better weather windows

🧥 Preparation

• What to wear today
• Whether to bring umbrella
• Extra commute time for icy conditions

Logging

Logs are stored in logs/smhi_weather_mcp.log with:

• 1 week rotation
• 1 month retention
• INFO level and above

Troubleshooting

Server doesn't start

1. Check dependencies are installed
2. Check logs in logs/smhi_weather_mcp.log
3. Verify correct directory

No data returned

1. Check coordinates are within Sweden (lat: 55-70, lon: 10-25)
2. SMHI API might be temporarily down
3. Check logs for specific errors

Weather seems outdated

• SMHI updates forecasts every few hours
• Check "Forecast updated" timestamp
• Re-run the tool to fetch latest data

Credits

• Weather data: SMHI - Sveriges Meteorologiska och Hydrologiska Institut
• License: Creative Commons Attribution 4.0 International
• Built with: FastMCP

License

MIT License

Note: SMHI data is used under CC-BY 4.0 license with proper attribution.