iPhone: Weather report APIs library

I am planning to add weather report for selected country->state->city, fo开发者_运维技巧r daily, weekly, monthly averages. I have googled it and also went through couple of discussion on stackoverflow threads and I got confused! Could anyone please tell me if there is already Weather report APIs library available? What could be the best way to implement my requirements? I am just expecting overview so that I don't chose wrong path.

Thanks.

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See WorldWeatherOnline.

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I compiled a set of information about different weather APIs looking for a similar solution. My general consensus was the WorldWeatherOnline seemed to be the best bang for the buck (free) and seemed pretty feature rich.

http://michaelwelburn.com/2011/11/02/comparing-weather-apis/

UPDATE (12/18/2013): This response was from 2011, since that time some different providers have made updates. I tried to keep the link semi-up to date, but you'll want to take the list provided and do your own research.