Higher humidity and a rain shower helped firefighters battle a wildfire that has burned more than 1,000 acres in northern Arizona on Tuesday, officials said.

Hundreds of firefighters from multiple local, state and federal agencies were combating the so-called Museum Fire, just north of Flagstaff in the Coconino National Forest, that broke out Sunday morning.

"We have close to 600 personnel on the fire right now as we speak,” incident commander Rich Nieto told reporters Tuesday morning. "I expect as we go further with this, that'll go up."

The fire has not claimed any structures, and no injuries have been reported, Nieto told a community meeting Tuesday evening, to applause. Arizona Gov. Doug Ducey on Tuesday declared a state of emergency in Coconino County.

By Tuesday evening the fire was 10 percent contained. Authorities Tuesday morning originally estimated 1,800 acres had been burned, but by the evening that number had been revised to approximately 1,400 acres, officials said, adding that smoke and weather have affected the ability to get an accurate estimated size.

Firefighters took advantage of favorable weather conditions to conduct “burnout operations” on the north side of the fire, and helicopters dropped water to cool hot spots within the fire perimeter, a news release Tuesday said.

Residents of 5,000 nearby homes were under "pre-evacuation" orders as firefighters dig in for a suppression effort that'll likely take days.

Operations chief Todd Abel said earlier that firefighters were scouting the area’s intricate trail system to find the best places to deploy assets and save "values at risk."

"That includes homes, residences, infrastructure which is power lines, pipelines, any of that stuff out there and then obviously the watershed that’s also a huge part of those values at risk for the local community," Abel said.

But the weather is expected to help tamp down the fire, National Weather Service and incident meteorologist Robert Rickey said at a community meeting Tuesday evening.

A thunderstorm Tuesday afternoon moved over the fire and dropped anywhere from a half-inch to an inch of rain, he said.

"In fact, we’re looking at a very good chance of showers of thunderstorms each day this week," Rickey said. While lightning and flash flooding could be a possible concern for firefighters, he said that even without the forecast rain, humidities are up in the region.

Fire behavior analyst Rob Beery said at Tuesday's community meeting that fire was "quite active."

"What's burning out there is a lot of heavy dead and down [fuel]," Beery said, adding there is no fire history in the area where it is burning, "so there is a lot of fuel out there."

"But the outlook on this fire is pretty much, according to the models and the moisture we've been getting, the size of it probably won’t grow much. It's pretty much done what it’s going to do," Beery said.

Expectations are that it could grow 200 acres until it's fully contained, Beery said.

"If we do get a period of extended drying, it’s going to come back to life," Beery said. But the intensity of the fire could make the area more prone to flooding, he said.

The fire broke out about 11 a.m. Sunday; the cause has yet to be determined.