Smoke forecast
Where the smoke over Chicago was, and where the model sends it next. Scrub back 12 hours or forward 48. Every hour shown is a model estimate, not a measurement.
The scale is anchored to visibility, because that is the one reading you can take yourself without trusting a model. Distances are approximate.
The Loop skyline is sharp from Montrose Harbor, about six miles up the lakefront, and the horizon over the lake is a clean line.
The skyline still reads from Montrose Harbor, but it has gone flat and grey at the edges and the far shoreline is gone.
From the lakefront the Willis Tower is still there but soft, and the far end of the Loop is losing its outline.
From Navy Pier the near towers hold, while the tops of the tallest buildings, roughly a mile and a half off, fade into the haze.
The upper floors of the Loop towers disappear. From the river you can lose the Willis Tower entirely.
Chicago sits at the downwind end of a long corridor from the Canadian boreal forest. Most smoke here has traveled from fires in Ontario, Manitoba, or Quebec, riding northerly and northwesterly flow south across the Great Lakes over a day or more.
In late June 2023, smoke from Quebec wildfires pushed Chicago to among the worst air quality of any major city in the world for parts of two days. That event is why a lot of people in this city now check before opening a window.
The verdict at the top of this page answers that for Chicago specifically. It reads the forecast model over the city and states the level in plain language, from All clear through Smokeshow, alongside how far you can typically see at that level. Everything shown is a model estimate rather than a measurement at your address.
That is the headline answer above. Smokeshow reports a clear time: the first stretch of at least six straight hours where the forecast drops below the Hazy threshold and stays there. The six-hour rule exists so a single hour's dip does not get announced as the all-clear.
When Chicago air turns hazy outside of a local source, wildfire smoke is the usual reason, and it has almost always traveled. Scrub the timeline backward twelve hours to watch where the smoke over the city came from, and forward forty-eight to see where the model sends it next.
Most smoke events here originate in the Canadian boreal forest, in Ontario, Manitoba, or Quebec, and arrive on northerly or northwesterly flow after a day or more in transit. The map shows the plume rather than a guess: run the timeline backward and the path it took is visible.
The five-day strip above gives a day-by-day read, and the detailed timeline covers the next forty-eight hours hour by hour. Smoke forecasts are sharpest one to two days out and get fuzzier after that, so the page also shows where the models disagree instead of hiding the spread.
Look at how far you can see, which is the anchor the whole scale is built on. The landmark list above turns each level into a specific Chicago sightline, so you can check the forecast against your own window.
Where Chicago's smoke usually shows up first, and the places that share its air.
Ontario and Manitoba smoke usually reaches the Twin Cities a day before it reaches the Chicago lakefront.
Ninety miles up the same shoreline, on the same northerly flow. What Milwaukee gets in the morning, Chicago often gets by evening.
Most smoke in the eastern half of the continent is Canadian, and it is old by the time it arrives.
Smokeshow is for informational and educational purposes only. It is not health, medical, or safety advice. Forecasts are model estimates and can be wrong, sometimes by a lot. Descriptions of what you might smell, see, or feel are generalizations, not predictions about your body. For decisions about your health, outdoor activity, or air quality safety, rely on official sources like AirNow.gov, the National Weather Service, and your local health authorities, and talk to a medical professional about your own situation.