The National Weather Service, or NWS, uses over 80 colors to represent watches, warnings, advisories and statements issued for forecast zones. The different colors indicate these events on a map. The NWS recently improved the map colors, increasing the number from only 30 colors to over 80. The colors are grouped by hue, to indicate cold or hot weather, and the level of importance. The National Weather Service updates the map every five minutes, presenting all the watches, warnings, etc in effect at that time.
Warnings are issued for hazardous weather events occurring or having a high probability of occurrence, threatening life and property. A watch is issued for significant events, yet still uncertain of when and where it will take place. A watch gives enough time to prepare and seek shelter. An advisory is less serious than a warning, issued for special weather events which may cause serious inconvenience, or damage to property.
The List of Warnings, Watches and Advisories continues by clicking here.