Watch, Warning, and Advisory Definitions

Fire Weather Definitions

Fire Weather Watch
Fire Weather Watches are issued anytime the area has been dry for a week or two (or for a shorter period during spring green-up or after fall color), the National Fire Danger Rating System (NFDRS) is high to extreme, and critical weather conditions are expected within the next 48 hours. These critical elements are:
  • sustained winds averaging 15 mph or greater
  • relative humidity 25 percent or less
  • temperature 75°F or greater
Red Flag Warning
Red Flag Warnings are issued anytime there is an ongoing wildfire, or critical weather conditions will occur within the next 24 hours. These conditions are:
  • sustained winds averaging 15 mph or greater
  • relative humidity 25 percent or less
  • temperature 75°F or greater

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