The current MythWeather in Fiesty no longer works as MSNBC has changed their data format. In order to get a working version of MythWeather you must build from the new mythweather-revamp source, which I must stress is beta code.

Get All Requirements

Get everything that may be required to build MythWeather

sudo apt-get install build-essential 
sudo apt-get build-dep mythtv mythweather

Get the perl modules that are missing

sudo apt-get install libxml-simple-perl libsoap-lite-perl libdate-manip-perl libimage-size-perl libgraphics-magick-perl 

Get the Source

If you don't have subversion installed

sudo apt-get install subversion 

You need to check out the MythPlugin source from here

sudo svn co http://svn.mythtv.org/svn/branches/release-0-21-fixes/mythplugins

Compile the Source

cd mythplugins
sudo ./configure --disable-all --enable-mythweather --prefix=/usr
sudo make
sudo make install

Fix Script Permissions

Sometimes the Perl scripts do not get execute permissions, we need to fix this

cd /usr/share/mythtv/mythweather/scripts
sudo chmod +x *.pl

Configure MythWeather

MythWeather should now be installed, it is time to enter your MythTv Frontend in order to configure MythWeather.

Utilities/Setup -> Setup -> Info Center Settings -> Weather Settings -> Screen Settings

Choose the screens you want to show up in MythWeather, after choosing a screen make sure you move down to the Active Screens and choose a location for each one. When you are done you need to save your data by hitting your menu button, default is 'M'.