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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 They no longer offer a free API key to new users.
- 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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