Accuweather
U.S. weather information by zip code.
http://www.accuweather.com/uwp/weather

Weather Channel
Provides news and current information.
http://harvest.weather.com/hdml/sprint/index.hdml

Weather Underground
Find weather by city, state, or continent.
http://phone.wunderground.com:99/

WeatherWindow
Provides forecasts and alerts.
http://weatherwindow.com/index.hdml

WetterOnline
World weather including areas with "gorgeous" conditions. Also provides snow reports.
http://wap.wetteronline.de/en/i.wml

Yahoo! Weather
Current conditions and forecasts.
http://mobile.yahoo.com/weather