Google Weather API

iGoogle Weather Feed API hasn't yet officially support the xml feed of weather. Anyway it can be used by http://www.google.com/ig/api?weather=$city.

For example, you want the rss feed of shanghai:

http://www.google.com/ig/api?weather=shanghai

In the xml, you will get current conditions and 4-days forcast.

22 Possible condition icons:

chance_of_rain.gif
sunny.gif
mostly_sunny.gif
partly_cloudy.gif
mostly_cloudy.gif
chance_of_storm.gif
showers.gif
rain.gif
chance_of_snow.gif
cloudy.gif
mist.gif
storm.gif
thunderstorm.gif
chance_of_tstorm.gif
sleet.gif
snow.gif
icy.gif
dust.gif
fog.gif
smoke.gif
haze.gif
flurries.gif

Reference:

• https://groups.google.com/group/Google-Gadgets-API/browse_thread/thread/b614a974eb68580e/9712867fd64f4c64?lnk=gst&q=weather#9712867fd64f4c64
• http://dennisjaamann.com/blog/?p=49 
• http://www.web-spirit.de/webdesign-tutorial/9/Wetter-auf-eigener-Website-mit-Google-Weather-API
• http://wiki.wunderground.com/index.php/API_-_XML 
• http://www.duisburgfans.de/