LiveWeatherIcon completely re-envisions the possibilities of the weather icon. It replaces the icon with an animated, visual description of the current weather condition with the temperature and a short textual description overlaid on top.
In order to use this tweak you must be running iOS 7 or later and be using the iPhone 4s, iPhone 5 or iPhone 5s. For those of you that prefer the Yahoo weather app but still would like to have a live icon, you can install 'Yahoo! Weather is Better' and every time you click the Weather Icon it will redirect you to the Yahoo weather app.
You can grab LiveWeatherIcon from Cydia for $1.