I am posting source code for the weather report control that I am using on my Web site. It looks like this:
It fetches weather forecast data from a free XML Web service provided by US National Oceanic and Atmospheric Administration (NOAA). There is a lot of data there (wind speed and direction, humidity, precipitation, etc). I only used some of it. I believe the data is for US only so it won't work for every geographical location.
There is no copyright of any kind, feel free to use the code any way you see fit. If you don't like the code or markup, don't shoot me, I am only a C++ developer :-)
Updated version: http://blogs.msdn.com/mikhailarkhipov/archive/2006/06/12/628540.aspx