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The closest thing I found to the weather would be to alter something like this: http://modmyi.com/forums/iphone-news/322341-how-add-weather-widget-homescreen.html

I tried it, and it made my lockscreen & home wallpaper disappear. Looking at the responses you have to once again, drag your wallpaper into the folder, though I'm getting sick of doing so and I already have to since my clock modification does the same thing to my lockscreen wallpaper.

Other than that, the widget didnt show up at all, and it looks like another project that was left to rot.

So if anyone can figure it out and fix the wallpaper issues then you may be a step further.
 
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