RED FEATHER LAKES, Colo. (AP) – Aircraft and ground crews tried to snuff out a growing spot fire on Friday that erupted north of an 81-square-mile blaze that has destroyed or damaged dozens of homes and killed one person in northern Colorado.

One after another, big helicopters flew to nearby lakes and hovered over them, drawing up water through hoses before flying back to the 200-acre spot fire to douse the flames.

Authorities sent evacuation notices to about 300 phone lines in the area and told other people to be prepared to leave.

“I have my wife all packed up and ready to go, and I’ll right behind,” said Bob Pichi, who had received the warning to be ready.

Firefighters have been in a see-saw battle with the blaze since last weekend, extending their lines along the eastern flank but losing ground on the west and north sides as flames burn through a dry forest thick with trees killed by bark beetles.

“Mother Nature is being tough on us,” incident commander Bill Hahnenberg said. “She’s not going to win this thing. We’re going to keep working.”

The fire was listed at 15 percent contained on Friday. Hahnenberg said full containment could be two to four weeks away.

The fire has cost about $7.2 million to fight.

Firefighters contended with 20- to 30-mph winds Friday morning, and the National Weather Service reported lightning strikes over the fire area in the afternoon. There were no immediate reports of additional fires from the lightning.

Light rain fell north of the fire Friday, but it wasn’t clear whether any fell on the fire. Hahnenberg said higher humidity was expected to continue into the weekend, a boon to firefighters.

Humidity was below 10 percent when the fire started on June 9.

Investigators said lightning triggered the fire about 15 miles west of Fort Collins and 60 miles northwest of Denver. Since then, authorities have confirmed at least 48 homes were damaged or destroyed, and they have said the final toll will include at least 118 houses, barns and other buildings.

One person was killed when a cabin burned. Relatives identified the victim as Linda Steadman, 62.

The spot fire erupted Thursday afternoon on the north side of the Cache la Poudre River. Firefighters have been working to keep the fire south of the river and have extinguished other incursions, but the most recent one appeared to be more serious.

“There are potentially many houses at risk” north of the fire, Hahnenberg said.

Evacuation calls have been made to about 3,000 phones since the fire started, but authorities cannot say how many homes are involved. Evacuation orders have been lifted for about 1,200 of those numbers.

Nearly 1,400 personnel, 103 fire engines, five heavy air tankers and 18 helicopters were available to fire managers Friday.

The fire is burning on land owned by private parties and the U.S. Forest Service. Agriculture Secretary Tom Vilsack, who oversees the Forest Service, is scheduled to meet with fire managers on Saturday.

At least two other wildfires were burning in Colorado.

A nearly 16-square-mile fire near Pagosa Springs was 30 percent contained. Lightning started that fire on May 13.

A 30-acre blaze near Lake George in Park County was 50 percent contained. It started Wednesday and was also caused by lightning.

Separately, a fire believed to have been caused by lightning destroyed a house four miles outside Rollinsville on Friday. Gilpin County sheriff’s spokeswoman Cherokee Blake said no one was hurt.

Gov. John Hickenlooper signed an executive order Thursday banning open burning and the private use of fireworks throughout Colorado.