The vicious Carr Fire near Redding, California, has already torched more than 207,000 acres, an area larger than New York City, since igniting on July 23. Flames have destroyed more than 1,000 homes in and around Redding, a town 200 miles north of San Francisco and home to 90,000 residents. Carr is now the eighth most destructive fire in state history and the most destructive ever for Shasta County.

The fire has killed at least seven people. Carr was so large and so hot, it has created its own weather system and melted boats on Whiskeytown Lake. Residents reported seeing fire tornadoes, and the rising smoke and ash created towering, dark pyrocumulus clouds. As of Tuesday, the fire is only 65 percent contained, and firefighting costs have already reached $24 million.

One bit of good news is that all 60 people reported missing have been found, according to police.

The Carr Fire is just one event in an already devastating wildfire year in the United States, coinciding with vast blazes in other parts of the world, including the Arctic Circle. These fires follow a “global heat wave” of searing, record-setting heat as well as exceptional drought.

But how did this fire get so acutely bad?

A lot of variables to converged to create a sweeping conflagration like the Carr Fire, but in short:

It’s hot. It’s dry. It’s windy. Just about everything on the ground is flammable.

Lisa Wilkolak, a public information officer with the multi-agency firefighting unit battling the Carr Fire, explained that a red-flag warning was already in effect at the start of the fire, meaning the conditions for a blaze were ripe.

Despite some rainfall in the spring, the brush and forests around Redding dried out in the triple-digit temperatures this summer, turning grasses and trees into tinder. “California itself is still trying to recover from drought,” Wilkolak said. “We had some dry fuels.”

What the heck is going on with California wildfire situation? Vegetation moisture in many areas now at/near record low levels. Why? Persistently hotter than avg. temperatures, plus dry winter. Map via NW Clim. Toolbox: https://t.co/cbOMwqHBiy #CAwx #CAfire #CarrFire #RiverFire pic.twitter.com/mD2muQKL4f — Dr. Daniel Swain (@Weather_West) July 29, 2018

Like most wildfires, this one ignited due to human activity. Officials report that a “mechanical failure of a vehicle” was the cause of the fire. Swift air currents soon fanned the flames.

“We had very, very intense winds at the beginning of this fire,” Wilkolak said.

In the background, the climate is also changing. Average temperatures are rising, and the state of California is increasingly ping-ponging between periods of severe rainfall and extreme drought. The conditions in recent years have led to a massive tree die-off, and scientists expect more woodlands to dry out across the West, contributing to larger, more destructive fires.

The fire is now moving west of Redding and into heavier fuels like pine, fir, and cedar trees. Some of the evacuated residents are being allowed to return, but temperatures in Redding are still soaring to triple digits this week and no rainfall is in sight. That means fire risks will remain high.

More than 3,600 workers are battling the fire. Reporters at the Redding Record Searchlight have been doing a phenomenal job covering the blaze and have some of the best, most updated information, despite many being forced from their homes.