Fire Dynamics, Firefighting, Wildland Firefighting

Report: Erratic Fire Behavior in Wildland Fire That Killed 19 AZ Firefighters

According to a recently released summary of the Yarnell Hill (AZ) Fire, a combination of unpredictable weather, challenging terrain, and limited resources helped contribute to fire that killed 19 firefighters on Sunday, June 30.

The Arizona Division of Forestry released the report. The wildfire began on Friday, June 28, when lightning struck a tree in a remote area in Yarnell, Arizona. The fire did not spark initial concerns; firefighters were ordered to wait until the following morning to respond to the Yarnell Hill fire and other area lightning fires.

As the fire spread on Saturday, officials ordered assistance from inmate crews, engines, helicopters, and air tankers. The report states on the evening of Saturday, June 29, air support could not respond to the scene because of incoming thunderstorms and high winds. A DC-10 was available but not ordered because officials felt the steep terrain of the area rendered its services ineffective.

By 7:38 p.m. Saturday, the fire had grown to about 100 acres. When the 20-member Granite Mountain Hotshots team arrived at 8 a.m. Sunday morning, the fire covered 1,000 acres.

The Hotshots team battled 20-foot high flames and impending thunderstorms and heavy winds. The report gives a timeline of events, and says the storm hit between three and four in the afternoon on Sunday. This weather, combined with a limited availability of resources, stalled much-needed air support.

The storms made the wildfire uncontrollable, which prompted officials to request half of the available U.S. heavy air tanker fleet. This is a large request for a small fleet, and weather conditions had not improved at the time of the request. Because of these reasons, only one plane was sent. The lone plane was on its way to Arizona from California when engine troubles forced it to turn around.

According to the report, spokesman for the Arizona Division of Forestry Jim Paxon says the planes would not have saved the firefighters because winds were too strong.

As previously mentioned, the Hotshots team arrived Sunday morning and the storm pushed the wildfire out of control by 4 p.m. the same day. At 4:47 p.m., the team radioed that they were trapped and had to deploy their emergency shelters. Less than two hours later, 19 members of the 20-member team were found dead.

The only surviving member of the Granite Mountain Hotshots team was a firefighter assigned as the lookout.

The report did not explain why the team did not evacuate the area after heavy winds shifted the fire 180 degrees and into the firefighters’ path. It also did not say whether or not the Hotshots team was warned of the impending storm.

The fire was fully contained on July 10 after taking the lives of 19 firefighters and destroying more than 100 homes.

A national team of investigators is expected to release an initial report on the wildfire in about two months.

For more details on the report, visit and