Actionscript3 :: Flash - Send Querystring Arguments And Parse XML Feed?

I need to call a REST web service that provides an XML feed of weather conditions. I have 13 cities for which conditions are needed, and only 3 nodes for each city are required (vs. the entire feed). My very basic first attempt is as follows:

[Code]...

First, how do I parse the 3 nodes, and ? Next, is there a way to pass a different querystring argument for each of the 13 cities? Finally, how would I add these values to an FLV that's been imported and placed on stage? The FLV displays a geographical area and pans from east to west plotting cities as it goes. At each city plot, the 3 node values need to be "superimposed" onto the FLV.