Everybody talks about the weather, but nobody does anything about it. Except when they're building mashups. Or so it seems, given how often the 5 weather APIs in our directory get used by developers. While perhaps not as sexy as the latest social networking API, here at ProgrammableWeb we have evidence that developers value a good API for weather, having built over 70 weather mashups to date. What are the weather APIs?
Weather Underground API: The latest weather API added to our directory is from the service Weather Underground. This API provides real-time weather data for major cities around the world as well as highly local weather reports. Wikipedia notes that it is the "most of its information comes from the National Weather Service (NWS), as information from that agency is within the public domain by federal law" and that in 2008 it was the #2 Internet weather service. The open API does not require an API key.
yr.no API: yr.no is "the joint online weather service from the Norwegian Meteorological Institute (met.no) and the Norwegian Broadcasting Corporation (NRK). yr.no offers weather forecasts in English for more than 700,000 places in Norway and 6.3 one million places worldwide." This RESTful API offers a wide range of this data in XML.
WeatherBug API: WeatherBug is a full source weather provider featuring exclusive data from its own network of over 8,000 weather observation stations in the USA. The API gives you access to live weather conditions, forecasts and severe weather warnings for all US zip codes.
Weather Channel API: As the folks at the Weather Channel describe, "Since 1982, The Weather Channel has brought timely weather information to the world. Now you can include weather from The Weather Channel in your own application by signing up for access to our XML data feed. We'll enable you to search for a location and to integrate current conditions and the forecast for today and tomorrow in your application for free."
NOAA Weather Service API: NOAA, the National Oceanic and Atmospheric Administration, offers this SOAP-based API. As they note: "The National Digital Forecast Database (NDFD) Extensible Markup Language (XML) is a service providing the public, government agencies, and commercial enterprises with data from the National Weather Service’s (NWS) digital forecast database." It's a useful and reliable service, even if the site itself looks like it hasn't been updated in years.
And what fame and riches await if you're a developer using these sorts of weather web services? Well if you're lucky, you could end-up like David Schorr, creator of classic mashup WeatherBonk, a mashup that was ultimately acquired by the Weather Channel themselves.