WeatherFire Watch


So we're under a Red Flag Warning... what does that mean?

Posted at 9:13 AM, Mar 08, 2018
and last updated 2018-03-08 13:40:36-05

Something we hear a lot during brush fire season is "Red Flag Warning", but what exactly does that mean?

A Red Flag Warning is a fire weather warning issued by the local National Weather Service. It essentially means that the day's weather conditions will contribute to extreme fire behavior if a brush fire does start. Red Flag Warnings are issued on dry and breezy days with low relative humidity and gusty winds. There should be no outdoor burning when a Red Flag Warning is in place. 

Relative humidity is the ratio of the amount of moisture currently in the air relative to the amount of moisture needed for the particle of air to reach saturation, expressed as a percentage. When relative humidity drops below a certain point (usually around 35%), it helps to dry out brush that fuels fires. 

Wind is also a major contributor to brush fires. Wind supplies fuel for the fire both with additional oxygen and by furthering drying out brush. It also helps spread fires by pushing it across land at a faster rate and carrying embers that can spark additional fires elsewhere. Wind controls the direction the fire moves and can complicate fire-fighting efforts when it changes direction suddenly. 

With SWFL's seasonal drought starting to kick in with abnormally dry conditions developing across the region, brush fire season is expected to heat up as well. It is important to stay safe and smart with our dry conditions and heed the warnings issued by the Florida Forest Service and local National Weather Service offices.