I'd say the best weather app is the one that comes with a really good clock: e.g. Fancy Widget, or Beautiful Widgets, depending on which you prefer. Since Fancy Widget, with the Flip Clock style and H7C themes looks just like the HTC clock, that's what I use. Weather information is pretty detailed and links to even more if a weekly summary isn't enough.
Setting up the weather requires to use either a location, or a predefined zipcode. Obviously if you type in a zipcode, you'll never need to use GPS or network location, but it also won't change when you move about.
If you want a full weather only app I recommend checking out Weatherbug Elite.
If you like it BUY IT. Support devs of worthy apps
