PENDLETON — Wind gusts of up to 45 mph brought a haze of wildfire smoke and dust from Washington that blanketed Pendleton and the rest of the Columbia Basin on Monday, Sept. 7.

“There’s actually a couple of fires up there that are the main source of the smoke,” said Jim Smith, the observation program leader at the National Weather Service in Pendleton. “Winds are blowing pretty strong and are increasing from the north and it’s blowing the smoke from the Tri-Cities and into the basin.”

Early signs of the haze peeked over the horizon of the basin early Labor Day morning as winds picked up the pace by 11 a.m. on Sept. 7.

Smith said a cold front moving from the north and northeast picked up most of the dust in its wind gusts near Ridgeville, Washington, and brought it to most of the lower Columbia Basin. The hazy conditions reduced visibility to below one mile and led to the National Weather Service in Pendleton issuing a blowing dust advisory for the area until 8 p.m. on Sept. 7.

“Gusty winds may create hazardous driving conditions with periods of low visibility due to dust and smoke. Tree branches or loose items may be blown about and isolated power outages are possible,” the advisory stated. “Motorists should exercise caution, especially if towing or in a high profile vehicle. If you encounter low visibility due to dust while driving, safely pull over until conditions clear.”

According to air monitoring data provided by the Oregon Department of Environmental Quality, the Air Quality Index, which measures the amount of pollutants in the air, peaked in Pendleton at 123 by noon on Sept. 7. The air conditions were considered “unhealthy for sensitive groups” until at least 2 p.m. before falling back to “moderate levels.”

In a press release on Saturday, Sept. 5, the Oregon Health Authority issued a cautious reminder heading into the Labor Day weekend to be aware of the potential health impacts that wildfire smoke and other air pollutants can have.

“Smoke from wildfires is a mixture of gases and fine particles from burning trees and other plant materials,” the release stated. “Wildfire smoke and other forms of air pollution can increase the risk of exacerbating respiratory diseases, including COVID-19.”

The risks brought by smoke from wildfires outside the region were also joined by more regional risks of additional wildfires igniting in the dry and windy conditions. Due to these conditions, the National Weather Service in Pendleton issued a Red Flag Warning from 11 a.m. Sept. 7 until 11 p.m., Tuesday, Sept. 8 due to “extreme” fire risks.

“As you recreate this Labor Day, take care with grills, fires, and flame,” a flash alert from the weather service stated. “Don’t park vehicles on dry grasses. Use spark arrestors on off-road vehicles. Fully extinguish cigarettes and flame. Obey local rules regarding campfires and consider foregoing a campfire even if allowed.”

The Umatilla National Forest and elsewhere are currently under Phase B restrictions from the U.S. Forest Service due to the “extreme” conditions, meaning campfires are only allowed in designated campgrounds and chain saw use is prohibited.

Extreme fire conditions are characterized both by a higher potential for a wildfire to start and its ability to spread and burn quickly and intensely.

“Fires start quickly, spread furiously, and burn intensely. All fires are potentially serious,” the National Wildlife Coordinating Group states in its definition. “Development into high intensity burning will usually be faster and occur from smaller fires than in the very high danger class.”

While an advisory is in place for fire conditions until 11 p.m. on Sept. 8, the gusty conditions that brought the smoky and dusty haze and contributed to extreme fire risks are expected to leave the basin by the night.

“They should drop off late tonight,” Smith said of the wind gusts. “Tomorrow we’re only looking at 10 mph. Maybe a little bit higher in the afternoon. But today’s the day through this evening.”