(YARNELL, Ariz.) -- Dry thunderstorms laced with strong, erratic winds that shifted unexpectedly in the Southwest's high heat likely created the perfect storm that trapped and killed 19 experienced firefighters in Yarnell, Ariz., officials say.
The wildfire was started by a lightning strike on Friday, amid triple-digit temperatures and low humidity. It killed 18 of 20 members of the Granite Mountain Hotshot Crew on Sunday. The 19th firefighter who perished was from another group.
Lightning and wind, combined with little rain, make up a deadly combination in a state that is bone-dry. Seventy-five percent of Arizona is suffering from severe drought or worse.
"When those two collide, you get unexpected fire behavior and surprising fire behavior and explosive fire behavior," said Karen Takai, fire information officer at Sandia Ranger district in New Mexico.
The Yarnell fire has burned through 8,400 acres and none of it is contained. There are 18 engines, eight support water tenders and a total of 500 personnel on the scene.
An estimated 200 homes and other structures burned in Yarnell, and the Yarnell Fire Department and Yavapai County will continue to assess the community on Tuesday.
Air tankers continue to drop fire retardant on the flames, but experts say Sunday's tragedy won't keep them from sending men and women to the frontlines.
"It takes a firefighter on the ground digging a fire line that stops the advance of the fire," former U.S. Forest Service wildfire expert Jim Paxon said.
Tuesday is expected to be another punishing day for firefighters with heavy hearts, still mourning the loss of their fallen brothers. A high of 115 degrees is expected.
Sunday was the deadliest day for U.S. firefighters since 9/11, when 340 died in New York City. The Arizona Diamondbacks just happened to be in New York playing the Mets Monday night when both teams paid tribute to the hotshots.
A baseball jersey with the number 19 hung in each team's dugout with the name "Yarnell."
"We'll never replace what they've had to go through, but hopefully we can help them in some capacity," Diamondbacks manager Kirk Gibson said.
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