Wildfires explained: What makes them so hard to put out, and more questions answered

Thousands of wildfires ignite in the U.S. each year, and each one requires firefighters to make quick decisions, often in difficult conditions like high winds and lightning.

Crews and managers must determine when to bring in aircraft, what time of day is best to battle flames, whether to evacuate residents and even if certain fires should be extinguished at all.

In the West, which sees many of the country’s largest fires, they do all this amid the backdrop of prolonged drought and other climate change-induced conditions that have made wildfires more destructive. Other challenges include a century of reflexive wildfire suppression and overgrown forests, experts say, and communities that have crept into fire-prone areas.

Russ Lane, fire operations chief for the Washington state Department of Natural Resources, explains how some key firefighting decisions are made.