http://adds.aviationweather.gov is another great site. There are alot of new tools on there to make getting the big picture easier.
http://wwwghcc.msfc.nasa.gov/GOES/ is a great sattelite site with 1km resolution images, for when you want to close up pic of the clouds, updated every 15 minutes. Just click on the visibile link and then click over the area you want to see. Best visiable satelite pics out there.
