Google just added some great weather features to Google Maps, which you can read about on the Google Lat Long Blog. There are some cool features in there, and I’ll probably use it from time to time.
However, if you really want to dig into the weather, Google Earth is still your best bet. Not only does it include the features now found in Google Maps, but you have great features like cloud/radar animations, “sun” mode to show real-time global light and the combination of a few of those to make Earth look amazingly realistic from space.
A few months ago, we posted a detailed entry highlighting all of the great weather tools in Google Earth. Be sure to grab the weather tools KMZ file to be able to see everything in one place.