What States Have Air Quality Alerts? Now 18 States Plus Washington DC — 115 Million People Under Canadian Wildfire Smoke

UPDATE — Sunday, July 19, 2026: the smoke has pushed south into the Mid-Atlantic. Alerts now cover 18 states plus Washington DC and roughly 115 million people, with “very unhealthy” to “hazardous” air stretching from northeast Minnesota to southeast Virginia, per ABC News and CBS News. Washington DC hit Code Purple — very unhealthy for everyone, not just sensitive groups — with smoke visibly hazing the Lincoln Memorial. Canada now has close to 900 active wildfires, more than 200 of them out of control. The National Weather Service expects rain and storms to scrub the air across the Northeast and Mid-Atlantic this weekend, while the Midwest stays smoky longer.

Air quality alerts now cover 18 states plus Washington DC as Canadian wildfire smoke sweeps across the eastern half of the country, putting more than 100 million people under advisories. Here is the full state list, the cities with the worst air, when forecasters expect it to clear, and how to check your own ZIP code.

Which States Have Air Quality Alerts?

Alerts now span these 18 states and Washington DC, running from the Upper Midwest down the Ohio Valley and up the eastern seaboard:

Region	States under alerts
Midwest	Minnesota, Michigan, Indiana, Ohio
Mid-Atlantic	West Virginia, Virginia, Maryland, Delaware, New Jersey, New York
Northeast	Connecticut, Rhode Island, Massachusetts, Vermont, New Hampshire, Maine

Earlier in the week the total reached 19 states as the plume pushed further south. Alerts are issued and lifted daily — always check your local reading rather than a list.

Where Is the Smoke Coming From?

More than 800 wildfires are actively burning across Canada, with large clusters in Ontario near the Minnesota border, plus fires burning inside Minnesota itself. Northerly winds have carried that smoke south and east, which is why cities a thousand miles from any fire have been choking on haze.

Cities With the Worst Air Quality

These metros recorded AQI readings above 200 — the "very unhealthy" band — and at points topped global rankings for the worst air on Earth:

• Chicago
• Detroit
• Milwaukee
• Pittsburgh
• Washington, D.C.

Dangerous pollution also stretched into southern Ohio and West Virginia. For the Chicago picture specifically — where AQI spiked to 753 — see our Chicago smoke timeline.

When Will the Air Clear?

• Saturday afternoon: a storm system was forecast to begin scouring the Mid-Atlantic and Northeast.
• Sunday afternoon: northerly winds could push more smoke back in — but forecasters expected it to be far thinner than the plumes earlier in the week.
• Beyond that: as long as Canada's fires burn, any northerly wind pattern can bring it back. This is a season, not a single event.

How to Check Your Area (and What the Numbers Mean)

Use AirNow.gov — the official US government air quality site — and enter your ZIP code, or open its Fire and Smoke Map for a live view of plumes and sensor readings. Quick guide to the scale:

AQI	What to do
0–50 Good	Normal activity
51–100 Moderate	Very sensitive people should ease up
101–150	Kids, elderly, asthma — limit outdoor exertion
151–200 Unhealthy	Everyone should cut back outdoors
201+ Very unhealthy	Stay in, run air conditioning on recirculate

Is It Safe to Exercise Outside?

During smoke events, exercise is the risky part — hard breathing pulls fine particles deeper into the lungs. General guidance during elevated AQI:

• Above 100: move hard workouts indoors if you have asthma, heart or lung conditions.
• Above 150: everyone should skip outdoor running and cycling.
• Above 200: stay inside, keep windows shut, use a purifier if you have one; an N95 helps if you must be out.
• Watch for a cough, chest tightness or getting winded unusually easily — that's the signal to stop.

Part of a Bigger Summer

The smoke has collided with a punishing summer of extremes — from record heat to catastrophic Texas flooding, with forecasters also watching a possible Super El Niño for the fall.

What Does “Code Purple” Air Quality Mean?

Washington DC hitting Code Purple is the detail worth understanding, because the colour codes are not just branding — they map to a numbered Air Quality Index and they change who is supposed to stay indoors.

• Green (0–50) — Good. No precautions needed.
• Yellow (51–100) — Moderate. Unusually sensitive people may want to ease off outdoor exertion.
• Orange (101–150) — Unhealthy for sensitive groups. Children, older adults, and people with asthma or heart conditions should limit time outside.
• Red (151–200) — Unhealthy. Everyone can start to feel effects; sensitive groups feel them more seriously.
• Purple (201–300) — Very unhealthy. This is a health alert for the whole population, not just sensitive groups. That is the level DC reached.
• Maroon (301+) — Hazardous. Emergency conditions; everyone is advised to stay indoors.

The practical difference between Orange and Purple is who it applies to. At Orange, a healthy adult can usually go about a normal day. At Purple, the guidance is for everyone to avoid outdoor exertion — runs, sport, yard work — and to keep windows shut and run air filtration if available.

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