A new back-country fire near Beach Lake in Yellowstone National Park was estimated at 150 acres in size with zero percent containment Monday afternoon by the National Park Service. The Beach Lake Fire, discovered Sunday morning, is seven miles southwest of Bridge Bay campground and two miles south of Beach Lake in Yellowstone's interior.

Its cause is unknown, according to a National Park Service news release on Monday.

With the fire at 150 acres by Sunday night, it has had quite a run thus far, said Yellowstone Park Spokesperson Al Nash.

Due to several factors including location, fuel, weather conditions and the smoky impact to park visitors in places such as Fishing Bridge and Lake Village, the decision was made Sunday morning to suppress the fire, Nash said.

Gusty Sunday afternoon thunderstorm winds prompted the fire to move into the crowns and spread.

Increased afternoon winds associated with thunderstorms most likely will continue to move the fire into the crowns of the trees and cause it to spread, the release said.

Crowning is just what it sounds like: Fire infiltrates tree tops and jumps from one tree to the next.

On Sunday, two helicopters from the Gallatin National Forest, an air tanker from Helena, Mont., and a second air tanker from Pocatello, Idaho, were deployed to augment park firefighters and the park's contract helicopter in their efforts to suppress the fire, said a Park Service news release.

The three helicopters and two air tankers resumed suppression efforts Monday morning, and they will be joined by the Helena Hotshots and the Lewis and Clark Hotshots. They will work to direct the fire into meadows and toward the west side of last year's Arnica Fire, said the release.

There are 20 firefighters in a hotshot crew.

“They are the most efficient folks that we could put out on the ground,” Nash said.

Nash said the hotshots will either hike or be airlifted to the fire.

The release said helicopters would continue to dump water on the hottest spots.

Monday's weather forecast predicted a chance of afternoon showers or thunderstorms with gusty west winds and high temperatures in the upper 60s to low 70s. The humidity was predicted to drop to 18-24 percent, the service said.

At this time, fire danger is rated as moderate in Yellowstone, but the service anticipates more fire starts as forests continue to dry.

The lightning-ignited Doane Fire, discovered July 11 a few miles south of the East Entrance, remains at one-quarter acre, according to a Sunday update on inciweb.org.

“No roads, campgrounds or trails are closed because of this fire. It poses no threat to visitors,” said the Park Service.

Ditto for closures on the Beach Fire, but the service said smoke may be visible when the fire is especially active.