At least six wildfires are burning in the state of Colorado this week, bolstered by hot, dry winds and no rain in the forecast. The conditions are so ripe for fires this week, officials are preemptively shutting down parks and forests.

The 416 fire, just north of Durango, Colo., has forced residents of about 2,000 homes to evacuate since it started June 1. The fire doubled in size over the weekend and, as of Monday night, had burned more than 23,000 acres. It’s only 15 percent contained, according to the National Forest Service.

The weather is not going to improve for firefighters through at least Thursday. High temperatures are forecast to reach the 80s, and humidity will be 15 percent. Winds out of the west are expected to gust to 25 mph.

Rain is expected late Thursday into Friday. If that materializes, it could provide favorable enough conditions for firefighters to make more progress on containment.

The fire danger is so bad in the Southwest, officials are preemptively shutting down public parks and forests to prevent the start of new fires, which is rare and done only as a last resort, the AP reports:

National forests and parks in Arizona and New Mexico have already been shut down as precautions.
San Juan National Forest officials in southwestern Colorado planned to close hundreds of miles of trails and thousands of miles of back roads to hikers, bikers, horseback riders and campers as soon as Tuesday to prevent the possibility of an abandoned campfire or any other spark from starting a wildfire. It’s the first full closure of a national forest in Colorado since 2002, which was another very dry year.

The closure will remain until sufficient precipitation eases the fire danger.

Wildfires are almost always caused by humans, according to a recent study. Since 1992, 84 percent of all fires were ignited by human action — intentional or otherwise. From 1992 to 2012, “the human-caused fire season was three times longer than the lightning-caused fire season and added an average of 40,000 wildfires per year across the United States,” researchers wrote in 2017. On top of that, human-caused fires usually affect regions close to population centers. Natural wildfires tend to occur in sparsely populated areas of the Mountain West, the study showed.

Officials are still investigating the cause of the 416 fire.