This information is from the lat long Google Earth Blog......................
In the latest release of Google Earth layers, we're letting you play weatherman by publishing a slew of great, dynamic weather data.
If you're running the latest version of Google Earth, you'll notice a new "Weather" folder in the layers panel.
The "Weather" folder contains three sub-layers
Clouds -depicts a global satellite mosaic of clouds created on an hourly basis by our friends down the road at the Naval Research Laboratory in Monterey. For a special visual treat, try zooming in towards the clouds. You'll eventually find yourself below the clouds, at which point you can look up and see the cloud deck above you.
The "Radar" layer contains a near real-time Doppler radar image of the United States, updated every 15 minutes. This data is being fed to us by the folks at Weather.com.
Conditions and Forecasts
Weather.com is also providing us with observation and forecast data for nearly 50,000 cities worldwide. The current conditions are updated at least hourly (more often in some places), and the forecasts get updated once every few hours.