I have created a general weather lib that retrieve data from yr.no.

You can see an widget based on netvibes UWA on the left using the weather lib from yr.no. To test it stand alone you can access it from http://weather.larsolavtorvik.com/uwa.html and http://weather.larsolavtorvik.com/uwaStandalone.html. These classes are very general so it should be no problem using them on other weather providers too. To add more providers just retrieve the data like I do in weatherYr.php.

I have created a package with all the files I have used available for download here. They are released under GNU General Public License version 3.