what is red flag warning in weather?


Red Flag Warning Weather is a term used by the National Weather Service (NWS) to describe weather conditions that pose a significant risk of wildfire. Understanding Red Flag Warning Weather is crucial for people who live in areas prone to wildfires to take necessary precautions.


A Red Flag Warning is issued when weather conditions, including sustained winds, low relative humidity, and warm temperatures, create a heightened risk of fire danger. The NWS issues the warning when any of the following criteria are met:

  • Sustained wind speeds of at least 25 mph or wind gusts of 35 mph or more
  • Relative humidity below 15 percent
  • A combination of dry fuels, low relative humidity, and/or strong winds that create a high risk of wildfire


Red Flag Warning Weather is typically caused by a combination of weather factors that can lead to the rapid spread of fires. These factors include:

  • High temperatures: When temperatures are high, vegetation dries out, creating ideal conditions for fires to start and spread.
  • Low humidity: Dry air reduces the amount of moisture in vegetation, making it more flammable.
  • Strong winds: High winds can quickly spread fires, making them difficult to control.
  • Drought: Extended periods of drought can cause vegetation to dry out, creating more fuel for fires.
  • Lightning: Lightning strikes can start fires in areas with dry vegetation.


To reduce the risk of wildfires during Red Flag Warning Weather, it is essential to take necessary precautions. These precautions include:

  • Avoid outdoor burning: Do not burn yard waste, trash, or debris during Red Flag Warning Weather conditions.
  • Follow local burn bans: Many areas have burn bans in place during high fire danger periods. Follow these bans and avoid burning during these times.
  • Be cautious with campfires: If you must have a campfire, make sure it is in a designated area and that it is fully extinguished before leaving.
  • Report fires: If you see a fire, report it immediately to local authorities. Quick action can prevent the fire from spreading and causing more damage.
  • Create defensible space: Create a defensible space around your home by removing any flammable materials within 30 feet of the structure.
  • Be prepared: Have an emergency kit ready in case you need to evacuate quickly. Make sure you know the evacuation routes in your area.


Red Flag Warning Weather is a serious threat to areas prone to wildfires. Understanding the causes and taking necessary precautions can reduce the risk of fires and protect lives and property. By following local guidelines and being prepared, people can stay safe during these dangerous weather conditions.

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