The icons for the weather forecast (sun, clouds, rain, and thunderstorms) are all embedded in the LCD window; only the current weather condition is lit up. The icons flash every second--for example, when it is cloudy, the blue outlined clouds will flash from one to another to indicate it is cloudy.
For the proper weather icon to display, you must select the correct icon along with the local time and other information when first setting up your weather station. To do this, press and hold the clock buton on the back of the main unit. First you will go through time settings. Then all the icons for weather will be lit. Use the arrow keys to choose your present condition among the four choices: sun, clouds, rain, and thunderstorms, then press clock to confirm.