Weatherstack

Real-Time & Historical World Weather Data API

Weatherstack provides real-time, historical, and forecast weather data for any location worldwide via a simple REST API. It delivers current conditions (temperature, humidity, wind, UV index, visibility), 7-day forecasts, and historical weather data going back to 2008. The API supports location lookup by city name, ZIP/postal code, IP address, or lat/long coordinates. For OpenClaw agents, Weatherstack is a reliable weather data backbone. Use it to power morning briefings with precise weather conditions, trigger alerts when severe weather is detected, or enrich travel planning workflows with forecast data. The structured JSON response makes it trivial to parse and embed weather info into Telegram or Discord messages. The free tier covers current weather for basic use, while paid plans unlock forecasts and historical data.

Tags: forecast, weather

Category: Weather

Use Cases

  • Power daily morning briefings with real-time weather conditions and forecasts
  • Trigger proactive alerts when temperature, UV index, or wind speed exceed thresholds
  • Enrich travel planning workflows with destination weather for upcoming trip dates
  • Log historical weather data for location-based analytics or agriculture monitoring

Tips

  • Cache responses aggressively — weather doesn't change every second. A 30-minute cache saves most of your monthly quota.
  • Use the 'query' parameter with lat/long for highest accuracy; city names can be ambiguous.
  • Combine with a cron job to fetch weather 2-3 times daily rather than on every user request.
  • The free tier works fine for personal agents if you cache well — 250 calls at twice daily is ~4 months of single-location weather.

Known Issues & Gotchas

  • Free tier is HTTP only — no HTTPS. Paid plan required for encrypted requests.
  • Free tier limited to 250 requests/month — easy to burn through with frequent polling.
  • Forecast and historical endpoints are paywalled. Don't build features around them on free tier.
  • The 'units' parameter defaults to metric (m). Use 'f' for Fahrenheit or 's' for scientific.

Frequently Asked Questions

Does the free tier include weather forecasts?

No. The free plan only provides current weather data. You need the Standard plan ($9.99/mo) or above for forecast data, and Professional ($49.99/mo) for historical weather.

Can I query weather by IP address?

Yes. Pass an IP address as the query parameter and Weatherstack will return weather for the geolocated position. Useful for personalizing weather data without asking users for their location.

Does Weatherstack support HTTPS on the free plan?

No. HTTPS/SSL encryption is only available on paid plans. The free tier uses HTTP only, which is a notable limitation for production use.