Can't you just look out of the window? It's a significantly better "user experience" than looking at your iDevice. It's timely, localised and precise by definition, it gets you away from your desk and the view is guaranteed to be more dynamic and informative. If you *open* the window you'll instantly know the temperature and humidity as well. If you do it often, you start to intuitively get a feeling for what to expect over the next few hours too, and will be more accurate than any broadcast weather service.
Sometimes I have just waken up and have the rolls down. Or I am somewhere without windows. But you miss the point: the point is the dynamic icons in apps you might need them.