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The weather portlet ships with two different weather data providers, Yahoo Weather and World Weather Online. Both services require an API key which can be retrieved by a self-service registration process.
Yahoo Weather
- Update 3/15/2016: Portlet must change to support Oath 1. See https://developer.yahoo.com/weather/.
- ToC limits usage to non-commercial use
- Key only required for location lookups
- 2000 invocations per day (Weather portlet caching reduces invocations per day)
- Much nicer icons
- Provides forecasts only two days into the future
- API key requests at https://developer.apps.yahoo.com (log in and select My Projects from your avitar image on top right)
World Weather Online
- Update 3/29/2016: Registration now looks like it gives a 60-day trial for Premium which is a different URL than the Free (and URL currently not supported by the Portlet). I was unable to get a free API key, though I emailed tech support to see if there was a way.
- Free to both non-commercial and commercial users
- Requires a key for both weather and location lookups
- Requires 15 minute caching of each feed (already the weather portlet's default caching strategy)
- Limit of 500 requests / hour
- Provides forecasts several days into the future (configurable)
- API key requests at http://www.worldweatheronline.com/register.aspx
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