The infrared or IR satellite view can be hard to read and often misleading when it comes to low level cloudiness. Keep in mind, the image is based on assigning a color code to temperatures in the atmosphere. The gray colors represent low clouds, yellow, purple and blue indicate higher level moisture, often associated with deep moisture areas and precipitation. To verify low cloudiness, look to the visible satellite image during the daylight hours.
Water Vapor is a great tool to see areas of moisture. Note: This product only shows upper level moisture, not low level, such as marine moisture producing our typical low cloudiness. The green colors represent the highest elevation moisture in the atmosphere, which often indicates the deepest moisture columns. Dry spots are shown with no imagery, meaning the brown color of the basemap. Looping the imagery will show rotation of upper level disturbances, often not seen by looking at IR satellite photos.
The visible satellite is a true photo taken of the clouds from a satellite. The only catch is, the photograph can only be viewed during the daylight hours. During the fall and winter months, use this image to identify valley fog and marine cloudiness. Remember to look at the image after sunrise and before sunset each day.
This radar display is courtesy of the portland National Weather Service doppler radar. Notice the bar legend on the right side of the display. Starting at the bottom, the tan colors up through - 0 - are indicative of ground clutter. Light blue is very light rain, green to yellow is moderate, up through heavy rain and possible hail starting with the red colors. Lightning is not indicated. If you are unsure of the display, loop the imagery for improved clarity.