Wildfire Safety GuideUnderstanding Wildfires

gettyimages-536120850-170667agetty imagesUnderstanding WildfiresLonger, hotter wildfire seasons are part of a growing trend, and while these unpredictable events tend to begin in rural areas, they can spread quickly to urban communities. The risk of these devastating scenarios is widespread, with potential impacts going far beyond structural damage. And while the 2023 wildfire season was less active compared to recent years, the increasing likeliness of fire weather conditions across the U.S. means understanding, preparation and planning are key. gettyimages-1097547990-170667agetty imagesWildfire Causes and AlertsHistorically, nearly 85% of wildland fires in the U.S. are caused by human activities and factors:

Backyard burning

Combustible engine machinery

Cigarette disposal

Fireworks

Recreational ceremonies

Unattended campfires

RedFlag warninggetty imagesOf course many wildfires are also caused by lightning, and what begins small can escalate swiftly under certain conditions. There are three types of alerts to signal the changing behaviors of wildfires: Fire Weather Watch – A watch means be prepared because critical fire weather conditions are possible, but not imminent or occurring.Red Flag Warning – A warning is a notice to take action because fire conditions are ongoing or expected to occur shortly. Extreme Fire Behavior – This alert means that a wildfire has already begun and is likely to rage out of control due to erratic fire behavior; evacuation orders may follow.raft-AdobeStock_169869092_PreviewAdobe stockWildfire Impacts: The Toll on Structures, Health and WildlifeA total of 4,318 structures were reported destroyed by wildfires in 2023; this includes 3,060 residences, 1,228 minor structures and 51 commercial/mixed residential structures. Even when homes and physical structures are not directly impacted by wildfires, the smoke from wildfires can travel vast distances, with the blazes affecting the physical, chemical and biological quality of essential natural resources and wildlife. Here are a few of the environmental and health impacts of wildfires:

Air quality – Smoke from wildfires can travel vast distances, affecting the air quality for people and animals many regions away. Eye irritation, difficulty breathing and runny nose are some of the more common health impacts of wildfire smoke, and for those suffering chronic respiratory or cardiac issues, the dangers can be fatal.

Water quality – The largest impact of wildfires is increase in stormwater runoff. With the loss of vegetation during a wildfire, the soil repels water, and new pathways are formed that transport debris and sediment to rivers, lakes and reservoirs. Along with debris, nitrogen and phosphorus concentrations from burned foliage run into water and lead to harmful algal blooms. Finally, flash floods resulting from wildfires introduce heavy metals from ash, soils and geologic sources into important waterways.

Wildlife – Wildfire impacts on grazing mammals and insects are particularly problematic, especially since the latter have a critical role in nutrient cycling and pollination. Pollutants in the water also make animals more susceptible to disease, and the fires can directly displace, injure and kill precious wildlife.

Wildfire Behaviors: How Wildfires Spread and Intensifytriangle_weather_topography_fuelsJust as oxygen, heat and fuel are frequently referred to as the “fire triangle” (i.e., the necessary ingredients for most fires), there is a “fire behavior triangle” that influences the spread and intensity of fire. There are three legs to the fire behavior triangle (image credit: NPS/C. BOEHLE):

Fuels – A fuel’s composition determines how quickly a fire can spread and how hot or intense the fire may become. Some vegetation, for example, contains oils or resins that promote combustion, while some live trees that hold large amounts of moisture can slow the burning process.

Weather – High winds, low humidity and hot temperatures are a major factor in the spread and increasing intensity of wildfires.

Topography – The shape of the land has influence on how fires behave. For example, north-facing rocky slopes will be harder to heat up and dry out, but fires that ignite at the bottom of steep slopes tend to spread much more quickly due to rising hot air and upward drafts.

raft-AdobeStock_510606741_Previewadobe stockTypes of Wildfires“Wildfire” is a term that encompasses three different types of fires. Since vegetation can vary at different levels of a forest, fires are classified by the level of the forest environment from which they burn.

Surface fires – These are the easiest wildfires to extinguish. They burn debris that tends to sit on the surface of the ground such as twigs, leaves and waste.

Crown fires – The most dangerous type of wildfire, crown fires burn in tree canopies. Since branches of trees tend to connect, these fires burn extremely hot and spread rapidly.

Ground fires – Also known as “subsurface fires,” ground fires may not exhibit a lot of flame but generally smolder as they burn ground fuels and consume buried vegetation.

This information is being provided for general informational purposes only. The Auto Club Group does not assume any liability in connection with providing this information.WildfiresUnderstanding WildfiresHome InsurancePreparing for a WildfireTravelDuring a WildfireAutomotiveAfter a WildfireD&RPrimary Threats to Home During a WildfireUser-guide