Upper level winds blew in more smoke from around 150 wildfires burning in Alberta and British Columbia on Friday, knocking air quality down to "unhealthy" levels and leaving the Mile High City with what was reportedly the second-worst air quality in the world, according to IQAir.com.
"If you’ve ever been in this, it’s just tough," says FOX Weather Meteorologist Craig Herrera. "You don’t want to be outside, even driving through it can be tough."
As those wildifires continue to burn in Canada, the jet stream and those prevailing winds will bring into the northern tier of the United States.
The Colorado Department of Public Health and Environment and the National Weather Service have issued Air Quality Alerts for the region that are in effect through at least Saturday afternoon. Officials warn of aggravated cases of heart and lung disease for those who suffer those ailments and increased respiratory effects for even healthy people.
"People with heart or lung disease, older adults, and children should avoid prolonged or heavy exertion; everyone else should reduce prolonged or heavy exertion," the CDPHE warned.
Elsewhere across the country, a large plume of wildfire smoke has been chasing a cold front pushing east across the eastern Great Lakes and Ohio Valley, dropping air quality into the moderate or "unhealthy for sensitive groups" category, including Indianapolis and around Toledo, Ohio.
Forecasts indicate this narrow plume will continue to push east into the Northeast later Saturday along the cold front, briefly knocking air quality down in the front's wake. Meanwhile, air quality should improve a bit in Colorado as Saturday progresses.
Renewed wave of smoke likely in Northern Plains over the weekend
As we push one plume of smoke off to the east, forecast models indicate a renewed plume of wildfire smoke will cross the Canadian border and into the Northern Rockies and Northern Plains later Saturday into Sunday.
"As those wildifires continue to burn in Canada, the jet stream and those prevailing winds will bring into the northern tier of the United States," Herrera said.
Lingering batches of smoke from the last week will hang around the Midwest and Mississippi River Valley.