On Thursday, July 16, the Cleveland Air Quality Index reached at least 681, well pass the 300 hazardous level. See the hazardous level for Cleveland on this NBC Nightly News map (far right side) on 7/16 at the 10:20 time. When I saw that I was shocked, as the AirNow.gov Maroon hazardous level begins at an AQI of 300.
Cleveland.com also did an article on the event, reporting the air quality reaching 594 at 3 p.m., after passing into the hazardous category by noon Thursday.
Hazardous is the highest of the AQI’s six categories. At that level, the entire population is more likely to experience health effects and should stay indoors and keep activity levels low, according to AirNow.gov....
At hazardous levels, everyone is more likely to experience health effects. Residents should stay indoors, keep activity levels low and watch for symptoms such as wheezing, coughing, chest tightness, dizziness or burning in the eyes, nose or throat.
Keep windows closed and, if possible, run air conditioning with a MERV-13 or higher-rated filter. Avoid candles, fireplaces and other activities that can add smoke or particles to indoor air.
https://www.cleveland.com/weather/2026/07/see-northeast-ohios-dramatic-hour-by-hour-plunge-into-hazardous-air-thursday.html
https://www.airnow.gov/aqi/aqi-basics/
Be alert to repeated wildfire smoke levels through August, according to Accuweather, even though levels are low today:
Canada wildfire smoke to be a periodic problem into August across Midwest, Northeast: Prevailing winds will direct more wildfire smoke from western Ontario into the Midwest and Northeast often well into August. Needed rain to put out the fires may be scarce.
There are 901 active wildfires in Canada, according to the Canadian Wildland Fire Information System. To date this year, there have been 3,951 fires that have burned 3 million hectares [7.41 million acres].
"...So far this year, 40,771 fires have burned more than 3.9 million acres across the United States," according to the (U.S.) National Interagency Fire Center newsroom. "Fires in the Northwest and the fires in northern Minnesota pose the greatest demand for firefighting resources. Resource assignments are being prioritized based on life and property risk, operational impact, and probability of success."
Many of the fires are burning in remote, hard-to-combat, unreachable areas, which then rely on wet weather to extinguish them. Where feasible, aircraft and ground crews work feverishly to safeguard communities from the flames.
Sometimes containment efforts work, but most attempts only slow the progress of the fires enough to allow people in the path to evacuate. In backwoods areas, where there are no roads or the distance is too far to fly in tanker aircraft with visual ground support, the fires are left to burn and let nature take its course.
Insect infestations (Spruce Budworm, Emerald Ash Borer and Mountain Pine Beetle) and drought have damaged or killed scores of trees, which then become potential fuel during droughts, lightning activity and when humans create ignition sources. Resins from certain trees and brush can accelerate fire ignition and spread.
Smoke is a product of fires, and its density depends on available fuels. Certain types of evergreen and deciduous foliage can emit much more smoke than simple grassland fires.
https://www.accuweather.com/en/weather-forecasts/canada-wildfire-smoke-to-be-a-periodic-problem-into-august-across-midwest-northeast/1913395
Winds fan the flames and carry smoke for hundreds and thousands of miles. How high or low the smoke is relative to the ground depends on atmospheric conditions, such as turbulence, humidity and precipitation. High-flying smoke may only cause the sky to appear hazy. Low-lying smoke can pose serious health risks and create dangerously low visibility.
The main driver of smoke from their origin points in western Ontario to the Midwest and Northeast is the prevailing jet stream dip over the eastern part of North America. Steering winds from the northwest will scoop up the smoke and whisk it southeastward.
I also was surprised by the 7/17 "All In" broadcast with Chris Hayes on MS Now. It's the only detailed broadcast about wildfires and climate change that I've seen anywhere in over a year.
https://www.youtube.com/watch?v=GEIFXjGROlM
Hayes noted how the Trump administration is spending billions to close offshore U.S. wind turbine developments.
https://thebulletin.org/2026/07/trump-spending-billions-of-taxpayer-dollars-to-keep-coal-alive-and-kill-clean-energy/
The Hayes program featured David Wallace Wells, author of "The Uninhabitable Earth: Life After Warming," and Senator Ed Markey (D-MA), one of the few U.S. Senators to emphasize the dangers of climate change.
https://www.amazon.com/Uninhabitable-Earth-Life-After-Warming/dp/0525576703
I doubt if you'll find any discussion like this on many Senator websites, certainly not on Ohio's Republican Senators websites who support President Trump's efforts to promote fossil fuel consumption, and not even on Democratic Senate candidate Sherrod Brown's websites. I've never heard or read a detailed explanation from Brown about why climate change should be a major political issue in the U.S.
https://www.markey.senate.gov/priorities/climate
Markey discussed how Trump in April of 2024 told the fossil fuel industry if they contribute $1 billion to his campaign, he would kill clean energy solutions.
https://www.theguardian.com/us-news/article/2024/may/09/trump-oil-ceo-donation
Hayes noted that climate change "is a problem that we'll be living with ... probably forever." He noted the difficulty of controlling Canadian wildfires.
Do a Google search if you want to read this article. The link is behind a paywall.
“It’s largely, not solely, due to human-caused climate change,” he said. “Warmer weather means longer fire seasons. In Canada, our fire seasons used to be fairly short, but they’re getting much longer. The warmer we get, the more lightning we see.”
Half of Canada’s wildfires are caused by lightning, he added, but they are responsible for 92 percent of the total forest surface burned — precisely in those impossible-to-reach areas.
https://www.nytimes.com/2026/07/18/world/canada/wildfires-canada-fire-fighting.html