After reading and installing, then ultimately uninstalling every weather app I have settled on a direct link on my home page to
http://mobile.weather.gov/port_mp_ns.php?CityName=Ypsilanti&site=DTX&State=MI&warnzone=MIZ075
It does not have instant updates the warn you of impending doom but with 2 clicks you can check yourself if you think one is imminent.
The thing that i loath about every free app I found and used was that you cannot load them to the sim. that means that a 4 to 8mb app is sucking resources all the time. Plus any add on widgets.
The best things about this is that it ia as accurate as you can get, it uses zero resources other than your data quotient, the maps are lightening fast as well as their animations, there are 10th day forecast, and there is a discussion area that speaks to their confindence on temps and events in locales, and its free.
Admittedly, I've only been using this for a few days but I like it so far. It is not pretty, with fancy hi-res wallpapers but it is the lightest and best fuctioning "app" out there imo.