After the sky and flight simulator, also 'last update of the content on Google Earth relates in some way the sky is the inclusion of new layer dedicated to weather latest version ( Google Earth 4.2 for free download from the official site ).
The layer is called "weather" and is structured in three tiers: clouds, radar, and weather conditions.
The data is updated on an hourly basis, while the forecasts are updated every 15 minutes.
data distribution of cloud cover are provided by the Naval Research Laboratory Monterey (California).
You can also download two files kml showing respectively: