Dying winds and 1,200 soldiers flown in to bolster weary firefighters in Yellowstone National Park have helped slow the blaze that was threatening two Montana towns at the park's northeast end.

"The threat to Cooke City and Silver Gate is essentially over," Fire Operations Chief Steve Frye said Tuesday."With the break in the winds the last two days, firefighters have had an opportunity to make some significant headway" against the Yellowstone fires that have blackened at least 350,000 acres in Wyoming and Montana, Frye said in an interview on ABC-TV's "Good Morning America."

Although winds of up to 70 mph over the weekend have died down, Frye said the burning acreage in the northeast Clover-Mist section of the park had increased to 215,00 acres, a jump over the 157,000 acres reported burning over the weekend.

In Idaho, National Guardsmen were called out to help attack a 700-acre fire.

Cooler temperatures and relatively light winds Monday helped firefighters battle the 37,000-acre Warm Springs Creek forest fire, southeast of Helena, Mont.

The 2-week-old fire, which damaged 13 homes and threatened scores of others, was the U.S. Bureau of Land Management's No. 1 priority Monday, said Jack Wilson, the agency's top official at the Inter-Agency Fire Center in Boise, Idaho, which coordinates firefighting resources nationwide.

The blaze in the rugged Elkhorn Mountains was burning in only a few spots inside the firebreaks Monday evening. Crews had hoped to contain it by Tuesday night, but after viewing the fire Tuesday morning they pushed that deadline back to Wednesday night, said fire information officer Bob Krepps. A fire is contained when it is surrounded by a firebreak.

Some of the 2,900 firefighters still might be sent home Tuesday, he said, while those remaining would finish establishing the firebreak and dousing hot spots that could flare if winds kicked up.

The infantrymen at Yellowstone, who arrived Monday from Fort Lewis, Wash., would work to keep the fires from spreading into commercial areas of the Shoshone National Forest and into Montana's Custer National Forest, said park spokeswoman Joan Anzelmo.

"At this point, having fresh help and able-bodied help is very important," park spokeswoman Joan Anzelmo said.

"Things are generally quiet, which is a good sign," she said. "But the forecast is calling for warmer temperatures, drier conditions and a potential for higher winds."

Despite help from the weather, Yellowstone's south entrance remained closed Monday, forcing visitors to travel about 150 miles to the west entrance. Three other entrances also remained open, officials said.

Several spots near the southern entrance were closed, including the Grant Village area, which contains a hotel, campground, visitor center and park staff facilities; and the Norris, Madison and Lewis Lake campgrounds.

The Pebble Creek campground, on the northern edge, also was closed.

In western Yellowstone, flames from the 91,700-acre North Fork fire destroyed 10 power lines on Sunday, and crews spent Monday wrapping power lines with protective material, removing excess fuels and hosing down buildings around Norris.

In southeast Montana, flame retardant was dropped by air to keep a fire in Kirby from burning a ranch home 6 miles south of Birney, said Don Kendall of the Department of State Lands.

Meanwhile, officials at Yellowstone National Park said fires there posed no immediate threat to residents of Cooke City and Silver Gate.

The two southern Montana towns are on the northeast border of the park and just south of the Absaroka-Beartooth Wilderness.