(CNN) -- Despite the holiday there was no rest for crews battling an Arizona wildfire that killed 19 firefighters over the weekend.
"We're not running out of resources," said U.S. Forest Service spokeswoman Suzanne Flory, adding there there is enough manpower on the ground to continue fighting the Yarnell Hill fire near Prescott.
"It's just the beginning of our fire season," she added. "And everybody is well aware of that. Folks that are here are going to have a long season ahead of them."
On average, workers are putting in 13- or 14-hour shifts but are able to sleep, shower and eat when they need to, she said. "We're very safety conscious and we're very careful about not overstressing or overworking anybody and making sure they get that rest that they need."
There are four helicopters battling the blaze, she told reporters.
Isolated thunderstorms are expected Thursday in the fire area, according to National Weather Service meteorologist Jim Wallman, who is there. "The biggest threat" from the storms, he said, is wind gusts that could reach 50 mph.
Rain actually could hurt efforts because people could get stuck in mud, he explained.
Thunderstorms also bring the possibility of lightning.
On Wednesday nearly 600 firefighters and support workers assigned to the fire took a brief break from their hard work to observe a moment of silence in honor of the 19 members of the Granite Mountain Hotshots, who died Sunday when the fire took a sudden, unexpected turn.
The pause coincided with the movement of a convoy of vehicles driven to the fire by the Granite Mountain team. The vehicles are being returned to Prescott, where they were based.
To start Wednesday's moment of silence, a loud alert tone sounded on firefighters' radios and an unidentified fire team commander announced, "As the crew carriers for the Granite Mountain hot shots leaves the Yarnell Hills fire and begin their journey home, all personnel in the incident will observe an operational pause, in observance of our fallen comrades."
The first official service to remember the lost firefighters will be held Tuesday in Prescott Valley. A ceremony is expected to begin at 11 a.m. local time at Tim's Toyota Center, according to CNN affiliate KPHO. The bodies are being guarded by members of the Phoenix Fire Honor Guard at the medical examiner's office in downtown Phoenix, the affiliate reported Thursday.