Additional firefighting resources arrived Sunday and more are expected to show up Monday following the Beaver Creek Fire's expansion of roughly 1,000 acres in just 24 hours. The blaze was estimated at 15,290 acres in size Sunday morning.

The National Weather Service issued a red flag warning on Sunday for the fire area, confirming that conditions are ideal for wildland fire combustion and rapid spread.

Winds on Saturday forced helicopters to halt their efforts to slow the fire's advance by dropping water on the flames.

Fire managers say any ember hitting the ground Sunday has an 80-90 percent chance of igniting. Humidity was expected to drop to 15 percent or lower, with sustained winds of 15-20 mph gusting to 40 mph.

"When humidity is very low, and especially when there are high or erratic winds, the Red Flag warning becomes a critical statement for firefighting agencies," fire managers said in a Sunday news release.

Jackson County Sheriff Gary Cure ordered evacuations for Parsons Draw landowners, who were advised of that possibility last week. The majority of landowners were already out when the order was issued Saturday. The fire has not reached Parsons Draw; crews continue to prepare for structure protection as the fire advances.

According to the release, the Beaver Creek Fire has been spread by embers lifted into the air and blown by the wind ahead of the main body of the fire. The fuel out in front of the fire is very conducive to ignition, and when that fuel is ignited and expands, it then puts more embers into the air.

Firefighters experienced that phenomenon Saturday when embers were blown across the 35 Road, establishing the fire on the east side of the road. The same thing was reported in the northeast area of the fire.

Resources on order will prepare to protect structures and improvements in the fire's path, according to fire managers.

The fire remains 5 percent contained, with 149 firefighters assigned to the blaze. Resources include two crews, 11 engines, a bulldozer and three helicopters.

The cause of the fire, burning roughly 24 miles north of Walden, Colo. and first reported Sunday, June 19, remains under investigation. Anyone with information on the source of the fire can contact U.S. Forest Service Law Enforcement Officer Hannah Nadeau at 307-343-2335.