About
World Weather Online delivers a unified suite of RESTful weather APIs designed for developers, businesses, and AI-powered applications. Since 2010, the platform has served accurate global weather data with a 99.99% uptime SLA and sub-300ms response times, making it suitable for mission-critical integrations. The API suite covers a wide range of use cases: the Local Weather API provides real-time conditions and up to 15-day hourly forecasts including temperature, humidity, UV index, and wind speed; the Marine & Sailing Weather API offers 7-day hourly swell, tide, and water temperature data for sailors, surfers, and shipping operators; the Ski & Mountain Weather API delivers base, middle, and top-elevation forecasts for ski resorts; and the Historical Weather API grants access to decades of records going back to July 2008. Additional endpoints include an Astronomy API (sunrise, sunset, moon phases), a Time Zone API, and a Location Search API supporting city names, IP addresses, postcodes, zip codes, IATA codes, and coordinates. A standout feature is its MCP (Model Context Protocol) server, which allows AI assistants such as Claude and Cursor to call weather data as native tools—no custom integration code required. Data is returned in both JSON and XML formats with multilingual weather descriptions, making it ideal for global applications. A free plan is available for getting started.
Key Features
- Comprehensive Weather API Suite: One platform covering local, marine, ski, historical, astronomy, time zone, and location search APIs in JSON and XML formats.
- Marine & Tidal Forecasts: 7-day hourly marine weather including swell height, tides, and water temperature — tailored for sailors, surfers, and shipping operators.
- Historical Weather Data: Access decades of weather records from July 2008 onwards for any city, town, or marine location via API or bulk download.
- AI Agent & MCP Integration: Available as a Model Context Protocol (MCP) server so AI assistants like Claude and Cursor can call weather data as native tools with just an API key.
- High Reliability & Speed: 99.99% uptime SLA and average response times under 300ms, with global HTTPS-secured endpoints suitable for production applications.
Use Cases
- Building travel and outdoor activity apps that surface real-time and forecast weather for any global location
- Integrating live weather context into AI assistants and RAG pipelines via the MCP server without custom integration code
- Powering marine navigation, sailing, and surf forecast applications with tide and swell data
- Analyzing historical weather patterns for climate research, agricultural planning, or insurance risk modeling
- Creating ski resort and mountain weather widgets with base, mid, and summit elevation forecasts
Pros
- Proven Reliability: 99.99% uptime SLA and sub-300ms response times make it dependable for mission-critical and real-time applications.
- Widest API Coverage: A single platform covers local, marine, ski, historical, astronomical, and time zone data — eliminating the need for multiple providers.
- AI-Native MCP Support: Out-of-the-box MCP server integration lets AI agents query live and historical weather without any custom glue code.
- Free Tier Available: Developers can start building immediately with a free plan before committing to a paid subscription.
Cons
- Free Tier Restrictions: The free plan likely includes rate limits and may restrict access to premium endpoints such as marine history or bulk historical downloads.
- Fragmented Pricing Across APIs: Different API products (marine, ski, historical) may require separate plan upgrades, increasing cost for multi-domain use cases.
- Limited Real-Time Severe Weather Alerts: Advanced severe weather alert features may not be as extensive as specialized meteorological services.
Frequently Asked Questions
Is there a free plan available?
Yes, World Weather Online offers a free plan that allows developers to get started and explore the API without upfront payment. Higher usage tiers require a paid subscription.
What data formats does the API support?
The API returns data in both JSON and XML formats, making it easy to integrate into virtually any tech stack or programming language.
Can World Weather Online be used with AI agents like Claude?
Yes. World Weather Online is available as an MCP (Model Context Protocol) server. AI assistants such as Claude, Cursor, and other MCP-compatible tools can call WWO weather data as native tools using just your API key.
How far back does historical weather data go?
Historical weather data is available from July 2008 onwards for cities, towns, and marine locations worldwide, accessible via the API or as a bulk data download.
What types of marine data are available?
The Marine Weather API provides 7-day hourly forecasts covering swell height and direction, tidal data, water temperature, wind speed, and wave period — suited for sailors, surfers, and commercial shipping.
