North American Cloud Patterns
The image above displays cloud cover across western North America. The Geostationary Operational Environmental Satellites (GOES) operated by NOAA took the image. That satellite can see in a variety of ways including visible light, water vapor patterns, and infrared. This image is looking at the temperatures of clouds across the Pacific. If you look at the scale on the right side of the image, you can see the scale. As you move up the scale, it shows colors of thicker clouds. If you see colorful areas, those are colder sections that will probably create more rainfall.
This image is great year-round to see storms that approach the west coast, but some times of the year are better than others. Winter months will display an increase in the number of storms approaching from the west. You may see colder storms moving in from the north from Alaska and you may see warmer storms move in from the south and Mexico. During years of high El Niño activity there will me many more winter storms moving in from Mexico.
This image displays the infrared channel data delivered from GOES satellites orbiting the Earth. The image has been enhanced electronically to provide a color scale that makes it easier to see areas of greater temperature changes. The image is updated every three hours. You may view the page sponsored by National Oceanic and Atmospheric Administration (NOAA) at http://www.goes.noaa.gov/index.html.
Link: Geostationary Satellite Server Color Enhanced Imagery (NOAA)