Why is weather forcasting so difficult?!

Answer 1

There are lots of ideas in here:

http://www.google.com/search?q=difficulties+in+weather+forecasting&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

Answer 2

And here is a collection of a science writer's articles that address some aspect of climate change, even sometimes whether to believe it or not!

http://blogs.chron.com/sciguy/archives/climate_change/