The deadliest fire in the U.S. in 80 years that claimed the lives of 19 members of the Yarnell, Arizona, fire squad, was sparked by lightning Friday, Arizona state fire officials said in a statement. An estimated 200 homes were also destroyed.
The fire spread some 8,000 acres on Sunday amid triple-digit temperatures, low humidity and windy conditions, state forestry spokesperson Carrie Dennett told CBS News.
"The high temperature was a 100 degrees, the relative humidity was bone-dry, about 10 percent or less during the day. The winds were fairly calm and predictable in the morning but then in the mid-to-late afternoon thunderstorms started to develop around that area which means not only was there lightening but the winds became very gusty and very unpredictable," said meteorologist Jeff Berardelli of CBS station WFOR, to CBS News.
Triple-digit heat fueled the out-of-control blaze in a forest northwest of Phoenix.
Dry grass near the communities of Yarnell and Glen Isla fed the fast-moving blaze, which was whipped up by wind and raced through the homes, state forestry spokesperson Art Morrison told The Associated Press.
"We saw wind gusts up to 30-35 mph and that made the behavior of the fire very unpredictable and probably caught them [the firefighters] off guard," said Berardelli.
Not much relief is in sight over next couple of days as temperatures are expected to remain above normal.
The National Weather Service says this heat wave is likely to be in the top five heat waves of the century.