What is a Red Flag Warning?
Jul 18, 2014, 3:23 PM | Updated: 3:23 pm
(AP Photo/The Tri-City Herald, Matt Gade)
The Washington wildfire season is here. Have you noticed the number of roadside fires in western Washington the past few weeks? July and August are usually our warmest and driest months of the year. As a result, fire danger usually reaches its peak and remains elevated even with quiet weather in place.
There are three factors in wildfire behavior: fuels, topography and weather. The warm dry weather results in drying fuels like grass, shrubs and trees making them ready to accept fire. Signs entering state lands, national forests or parks display the current fire danger level. Topography does not change. So weather plays a key variable role in wildfire behavior.
Once in a while, weather plays a serious aggravating factor in fire behavior. Those are the days when the National Weather Service will issue a Red Flag Warning.
A Red Flag Warning is a weather warning with an emphasis on firefighter safety. Though warm dry summer weather increases fire danger, a Red Flag Warning is reserved for three special weather scenarios that aggravates wildfire behavior – strong winds and low humidity, a very dry and unstable atmosphere, and lightning.
Before a Red Flag Warning is issued, fire danger is already high and everyone needs to take precautions with fire and flammable materials. Is a Red Flag Warning a measure of fire danger? The answer is no. Fire danger is driven by the dryness of fuels like grass, shrubs and trees.
Does a Red Flag Warning mean that everyone should be careful with fire? Yes. Fire danger is already high and now the weather is elevating fire behavior conditions further. Is fire danger over when a Red Flag Warning ends? The answer is no. It means weather is no longer an aggravating factor with firefighting efforts. Yet fire danger remains high and everyone should be vigilant with flammable materials.
So what is a Fire Weather Watch? Adverse firefighting weather conditions are anticipated in a day or two in advance. A Watch usually precedes a Red Flag Warning but not always.
Now you know what a Red Flag Warning and Fire Weather Watch means. Be careful with fire and flammable materials this summer. In Washington state, about 70 percent of wildfires are human caused. No one wants any more human caused wildfires.