Canadian wildfires create hazy skies in area

Hazy skies across Missouri and other states in the Midwest are being blamed on smoke moving across the area from forest fires in Canada.

Smoke from wildfires burning in Canada's Alberta and Saskatchewan provinces has traveled as far as 1,600 miles south, weather officials have said, pushed by a jet stream dipping into the United States.

Satellite observations from the National Oceanic and Atmospheric Administration show an expansive area of light- to heavy-density smoke moving southeast into lower portions of Canada, with denser smoke moving deeper south into the Mississippi River Valley and Tennessee Valley, according to a report. It went on to say the wildfires still were producing heavy smoke.

Smoke from wildfires in northern Saskatchewan blew as far south as Tennessee, with a thick haze extending through much of North Dakota, South Dakota, Minnesota, eastern Nebraska, Iowa, Illinois and Missouri.

Those layers of heavy smoke also are the reason some may have noticed a particularly red or orange hue when they glanced at the sun the past few days, weather officials said. The smoke causes certain wavelengths of light to be scattered but allows longer wavelengths on the red end of the spectrum to pass through, resulting in particularly vivid sunsets for those watching the skies.

"There's a ton of smoke from Canada across the northern Plains," said Bill Borghoff, a weather service forecaster in Chanhassen, Minnesota. "The strong jet stream makes for a perfect setup to bring all this smoke to the south."

Dry conditions, lightning and strong winds have contributed to the many wildfires in Canada, according to the National Weather Service.

The smoky conditions caused county health departments in Des Moines, Iowa, and Omaha, Nebraska, to issue warnings, urging people to refrain from exercising outside. People with heart or lung diseases and the elderly are at increased risk of health problems that would require hospital emergency room visits, officials said.

Brad Fillback, a weather service forecaster in Johnston, Iowa, said the smoke likely is reducing daytime temperatures by a few degrees but allowed for less cooling at night.

"It's acting a bit like clouds," he said.

The smoke should shift eastward by Thursday, first spreading toward the Great Lakes but later reaching as far east as New England.

As it moves east, the smoke should be less dense, as high-altitude winds cause it to "fracture," Borghoff said.

It's unclear how long the fires in Canada could burn, and Borghoff said wind conditions could bring more smoke into the Midwest in a couple weeks.

Southeast Missourian staff reporter Samantha Rinehart contributed to this story.