Space Science and Engineering Center website by University of Wisconsin-Madison's Graduate School shows a real time animation of the cloud cover over the North America continent. It gets the satellite images and shows animation by stitching those images together. With the help of it you can get an idea of what weather is going to be like in coming hours by taking a look at the forming clouds, storms near your city area.
You can see weather for the hours passed and at the end of day you see what it looked throughout the day. We all know its difficult to predict the weather in our present day world but this really shows how the cloud cover is changing continuously over North America.