I tried this out the other day but to be honest I'm not a fan for the simple fact you are stuck with yahoo weather. If they were to implement the option to select from other weather services, like accuweather for example, I would definitely give it a whirl but I do not want my lockscreen saying one weather and my homescreen saying another because they are two different apps with two different providers.
Because of this I'll stick to Beautiful Widgets, I have my custom lockscreen version of the widget I want and a custom homescreen version, both display the same weather and both open the same full weather application when I click them.
Again, not knocking this widget, I used the cm lockscreen mod for weather on 4.1.2 but the lack of options on the weather provider killed it for me even then.
Another thing that would be great for them to implement is the ability to choose what app opens when clicking on the weather, clock and calendar. BeWeather and Beautiful Widgets both have this as well as dozens of other weather/clock apps.
Anyway, just my 2 cents.
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