What is a Red Flag Warning?

A Red Flag Warning is a type of fire weather warning used by meteorologists to alert the public of extreme fire conditions in which extreme fire danger exists. These weather conditions typically include high temperatures, low relative humidity values, strong winds, and dry fuels, each of which can contribute to extreme fire behavior. Red Flag Warnings are issued when weather conditions are expected to coincide with any combination of these criteria in order to provide emergency management organizations and the public with advanced awareness of the onset of potentially dangerous wildfire conditions.

Understanding the Criteria Behind a Red Flag Warning

The criteria for a Red Flag Warning is usually the same for all regions. The dry fuels refer to vegetation such as grass, leaves, branches, and other debris. The temperature criteria for a Red Flag Warning is usually set by the local National Weather Service office, with values ranging from 75 to 84°F. The relative humidity, which is the measure of moisture content in the air, typically must be in the teens or lower. Finally, the wind criteria for a Red Flag Warning is usually defined to be 25 mph or higher, sustained over a one-hour period. The parameters assessed when determining if the criteria to issue a Red Flag Warning has been met are those that contribute to extreme fire behavior.

The Purpose of Red Flag Warnings

Red Flag Warnings are issued to inform the public and emergency management personnel of the imminent danger of wildland fire. With advanced knowledge of the potential wildfire danger, emergency management personnel can take steps to better secure and protect their communities by reinforcing fire lines, implementing burn bans, and encouraging public behavior that can help reduce the likelihood of an uncontrolled wildland fire. By alerting the public to extreme fire danger, individuals can modify their behavior by perhaps refraining from any outdoor activity that could potentially spark a wildfire and refrain from burning any type of debris.

In summary, Red Flag Warnings are issued by meteorologists to alert the public of extreme fire conditions in which extreme fire danger can exist. This type of fire weather warning is predicated by high temperature, low relative humidity values, strong winds and dry fuels that can all contribute to extreme fire behavior. Red Flag Warnings are issued to give public and emergency management personnel advanced warning of the onset of potentially dangerous wildfire conditions; this in turn, allows these organizations and the public to take proper steps to protect and secure their communities.