WeatherIcon was updated earlier today with long-awaited iOS 6 support for the iPhone and iPod touch. The free jailbreak tweak changes the default Weather.app icon to a dynamic one that automatically changes based on your local weather forecast.
WeatherIcon shows both the current temperature and weather condition, so long as your device is connected to Wi-Fi or a cellular data network. To get this tweak, search for WeatherIcon 6 in Cydia on the ModMyi repository. Do you find this tweak useful?