Detroit air quality ranked worst in world again Friday

The air quality in Detroit ranked worst in the world again Friday morning, according to IQAir. 

More than 850 wildfires are burning across Canada, and the smoke continues to blanket us in southeast Michigan. 

Detroit worst air quality in the world 

By the numbers:

IQAir ranked Detroit with the worst air quality in the world Friday morning:

• Detroit (438)
• Chicago (382)
• Washington, D.C. (257)
• New York (175)
• Toronto (172)
• Jakarta, Indonesia (159)

Detroit's air ranked worst in the world yesterday as well, alongside several other Midwestern cities including Minneapolis and Chicago. 

Air quality ratings

Dig deeper:

The Air Quality Index score ratings are:

• 0-50 GOOD — Little to no risk
• 51-100 — MODERATE — A small number of unusually sensitive people may have health concerns
• 101-150 —  UNHEALTHY FOR SOME — People with heart/lung disease, older adults and children should limit outdoor activities
• 151-200 — UNHEALTHY — Everyone should limit outdoor activities, unusually sensitive people should remain indoors.
• 201-300 — VERY UNHEALTHY — Everyone should remain indoors as much as possible.
• Any score beyond 301 is HAZARDOUS.

How long will the smoke last? 

Timeline:

Conditions should improve dramatically tonight, with much cleaner air settling in by Saturday morning as southerly winds push the smoke plume north and west.

• Friday, at noon, the forecast is for ‘Very Unhealthy’ in the 201 to 300 range.
• At 5 p.m. Friday, the forecast is for 'Unhealthy' in the 150 to 200 range.

For the rest of the evening, metro Detroit will stay in that range with the number gradually lessening closer to the 150 mark.

Saturday we will wake up with much clearer skies, but the haze is expected to return in the afternoon and evening, though much less severe. 

Dig deeper:

Storm chances return Friday as well, although coverage stays isolated this evening. 

A better opportunity arrives Saturday around midday, with scattered showers and storms moving in midday before tapering off around 5 p.m. 

A few of those storms could produce stronger wind gusts, but only on an isolated to scattered basis.

And we could see some so-called "dirty rain" because of the smoke. 

Where are the wildfires in Canada? 

Big picture view:

According to the Canadian government, more than 850 wildfires were active across Canada as of Thursday, with 29 new fires reported this week. Most of the fires designated as "out of control" were in western Ontario, north of Minnesota, and in northern Saskatchewan. But multiple active fires are reported in all provinces. 

Winds are carrying the smoke southeast from Ontario down to Illinois, Minnesota, Michigan, New York, Wisconsin and even parts of Maine.

RELATED: Where are the Canada wildfires burning?

Can I go outside in the smoke? 

What they're saying:

It is recommended that, when possible, you avoid strenuous outdoor activities, especially those with heart disease and respiratory conditions like asthma.

Watch for symptoms including wheezing, coughing, chest tightness, dizziness, or burning in nose, throat, and
eyes.

You can help reduce air pollution by limiting activities, such as outdoor burning and use of residential wood burning devices.