WeatherBug for iPad Great dashboard feel for all things weather - current conditions, forecast, hourly forecast, even local webcams.

The Weather Channel for iPad Less of a dashboard and more of an app with separate screens for forecasts, maps, etc. Very clean, simple UI

AccuWeather for iPad Best graphics of the bunch, with a very minimal interface. Not crazy about the menu button, which is as big as a nickel and sits on top of maps, forecast data, etc. Hourly forecast UI, designed like a clock, is sort of fun.