NEBO The Dobson Knob fire, burning in McDowell County, nearly tripled in size over two days as it grew to about 1,405 acres by Thursday morning and containment of flames was at 15 percent, a 5 percent increase from Wednesday, according to the U.S. Forest Service.

Flames began Sunday near the community of North Cove, north of Marion in McDowell County, west of Dobson Knob, along U.S. 221 on private land in the Grandfather Ranger District of the Pisgah National Forest. The fire was initially estimated at 125 acres and grew to 200 acres by Monday evening. By Wednesday morning the blaze had spread across 550 acres and was considered 10 percent contained, according to the U.S. Forest Service.

Officials are still working to determine a cause, said spokesman Bruce MacDonald with the Dobson Fire.

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State air quality officials issued a Code Orange Quality Action Day for the region for Thursday that could possibly continue through Friday.

An Action Day means particulate concentrations within the region may approach or exceed unhealthy standards. Area residents and visitors with respiratory sensitive conditions should take appropriate actions. Avoiding outdoor activities, keeping doors and windows closed and operating air conditioning systems are some common practices to avoid smoke inhalation.

Overnight Thursday a weak cold front is expected to pass through the area with a few isolated showers and thunderstorms. High pressure will build over the area tomorrow with sunny skies and light northerly winds but areas near the Dobson Fire,  in McDowell and western Burke counties including the communities of Marion, Nebo, and Linville, will likely have periods of smoke in the Code Orange range.

About 180 firefighters were battling the Dobson Knob fire as of Wednesday after a N.C. Forest Service Type 2 Incident Management Team took over fire management including suppression efforts and public information responsibilities.

Firefighters made good progress Wednesday as they completed burnout operations along the northern and western sides of the blaze. "We are trying to build on that success Thursday," MacDonald said.

As suppression efforts continue, firefighters were patrolling fire lines and extinguishing any hot spots on the western, eastern and northern sides of the fire.

Firefighters also continued structure protection along the west side of the blaze where about 35 homes and 10 minor structures are nearby and scouted for viable control options to continue increasing containment of flames, according to a news update from the U.S. Forest Service.

Structure protection was also in place for the Ashford and North Cove communities.

The chance of flames threatening structures decreased Wednesday, but structure protection remains a priority, fire officials said.

The Dobson Knob Fire began Sunday afternoon on private property off Old Linville Road in the North Cove Community.

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