Air quality has been a concern in Alberta this week as several wildfires burn in the northern parts of the province.

On Saturday, special air quality statements remained in place for much of Alberta, including Edmonton, Red Deer and most of northern Alberta. However, the air quality statement for the Calgary, Airdrie and Rocky Mountain House areas had been lifted.

READ MORE: Why does the sky look yellow during a wildfire?

The thickest smoke on Saturday morning extended from northeastern British Columbia through eastern portions of Whitecourt, Drayton Valley, Red Deer and much of southern Alberta. The foothills were expected to see improvement throughout the day Saturday, with the rest of southern Alberta improving later in the afternoon and evening.

Air quality was more of a concern in eastern portions of Alberta, with conditions expected to worsen Saturday afternoon and into the evening hours.

Northern Alberta was expected to remain enveloped by wildfire smoke through the weekend, according to Environment Canada.

READ MORE: Wildfire smoke can harm your lungs, your heart, and maybe even your mental health, research says

Alberta’s Air Quality Health Index is measured on a scale ranging from 1 to 10+. Anything from 1-3 is considered a low risk, 4-6 is a moderate risk, 7-10 is a high risk and 10+ is very high risk.

Edmonton’s air quality health index sat at a 6 late Saturday morning, a moderate risk. Conditions were expected to get worse throughout the day and reach a 10+ on the scale — a very high risk.

The air quality is expected to remain poor through the night Saturday.

During special air quality statements, people may find themselves coughing more or experience throat irritation, headaches or shortness of breath.

READ MORE: What to look for in a mask for wildfire smoke

Children, seniors and people with cardiovascular or lung disease such as asthma and COPD are especially at risk.

People experiencing difficulty breathing should stay inside where it’s cool and ventilated. Using an air conditioner may help. For more information, visit the Alberta Health Services website. </s> Thick smoke settled into southern Alberta Thursday, and continued to stifle air quality on Friday.

Thursday evening, the air quality health index in Calgary jumped from a 4 to 10 in a matter of three hours.

READ MORE: Wildfire smoke can harm your lungs, your heart, and maybe even your mental health: research

By Friday morning at 11 a.m., the AQHI had launched off the charts and to a score of 18.

According to Environment Canada’s Health Index, physical exertion and strenuous activities outdoors should be limited or avoided, especially for children, elderly and anyone with respiratory illnesses while the numbers are so high.

Large sections of northern Alberta are being consumed by wildfires and almost every day has brought new advisories and orders.

The fires are burning in multiple areas hundreds of kilometres apart, triggering evacuations of several communities in northwestern and north-central Alberta.

Here is a summary of the existing alerts and orders across Alberta.

Traffic issues such a road closures are posted to the Alberta 511 government website.

The smoke travelled farther south, prompting Environment Canada to expand special air quality statements to include the entire southern portion of Alberta.

READ MORE: Alberta wildfires: Evacuation alerts and orders in place across the province

Winds will continue blowing from the south over the weekend, which should help improve conditions in southern Alberta.

To stay updated with weather alerts in your area, download the Global News Skytracker weather app for iPhone, iPad or Android.

IN PICTURES: Smoke as seen from viewers around southern Alberta

READ MORE: Smoke from the Alberta wildfires is obscuring the sun in several U.S. cities

Refer to the Government of Alberta Air Quality Health Index website for the most current AQHI rating in your area. </s> People across much of Alberta woke up to grey skies and a strong burning smell in the air as smoke from northern wildfires drifted south overnight.

Environment Canada issued special air quality statements from the Edmonton region to the northern tip of the province.

Areas of central Alberta were also included, including Drayton Valley, Rimbey, Pigeon Lake, Lloydminster, and Wainwright.

A prediction map from FireSmoke.ca indicates the smoke will continue to flow south throughout Thursday.

READ MORE: Smoke fills Calgary skyline from wildfires burning in northern Alberta

Environment Canada said in central parts of the province, smoke is expected to move back north by Friday morning as the flow shifts to southeasterly.

The air quality across northern Alberta is expected to remain high on the Alberta Environment air quality health index (AQHI) all day.

Alberta Health measures the AQHI on a scale of one to 10, with higher numbers meaning a greater health risk.

Most of Alberta, including the Edmonton region, is expected to be at a six, or “moderate risk,” on Wednesday. Some areas to the northwest, including Grande Prairie, are forecasted to be higher on the scale.

Environment Canada said some people may experience increased coughing, throat irritation, headaches or shortness of breath due to the smoke. Children, seniors, and those with cardiovascular or lung disease, such as asthma, are especially at risk.

READ MORE: Climate change report warns of more extreme weather events in Alberta

People with lung diseases, such as asthma and COPD, can be particularly sensitive to air pollution and will generally experience more serious health effects at lower levels. Pollution can aggravate their diseases, leading to increased medication use, doctor and emergency room visits, and hospital visits.

Those with difficulty breathing are advised to stay indoors. Using an air conditioner that cools and filters air may help. The weather agency suggests if your home isn’t air-conditioned, consider going to a public place (library, shopping mall, recreation centre) that is air-conditioned.

According to Alberta Wildfire, there were 25 active wildfires across the province as of 10 a.m. on Wednesday.

Of those, six had been sparked in the last 24 hours and seven were considered to be out of control. Updated numbers are expected Thursday morning.

The fires are burning in multiple areas hundreds of kilometres apart, triggering evacuations of several communities in northwestern and north-central Alberta.

Mandatory evacuation orders are in effect for:
• Town of High Level and Mackenzie Country areas south/southeast of town
• Dene Tha’ First Nation communities of Bushe River, Meander River and Chateh
• Keg River, Carcajou, and all residents from the northern border of the County of Northern Lights to Township Road 922 (Notikewin Road)
• Wabasca and the Bigstone Cree Nation in the MD of Opportunity
• Chipewyan Lake Village in in the MD of Opportunity

READ MORE: Northern Alberta MD of Opportunity communities ordered to evacuate overnight due to wildfires

Experts have forecast a summer of high wildfire danger across Western Canada and have warned that climate change will continue to worsen fire seasons in the future. </s> Smoke from large wildfires in Canada's Alberta province has drifted into five U.S. states and is causing haze and air quality issues.

More than two dozen fires are burning in Alberta and 10,000 people have been forced from their homes.

The smoke has drifted into Montana, North Dakota, South Dakota, Washington state and Wyoming.

The government agency Alberta Wildfire reports the largest blaze is out of control about 450 miles (733 kilometers) north of Edmonton and has burned 887 square miles (2,300 square kilometers) of land.

The U.S. Environmental Protection Agency rated Helena's air quality as unhealthy Friday morning while the air quality in the Montana cities of Great Falls and Lewistown was rated as unhealthy for sensitive groups such as people with asthma or heart disease. </s> HELENA, Mont. (AP) — Smoke from large wildfires in Canada's Alberta province has drifted into five U.S. states and is causing haze and air quality issues.

More than two dozen fires are burning in Alberta and 10,000 people have been forced from their homes.

The smoke has drifted into Montana, North Dakota, South Dakota, Washington state and Wyoming.

The government agency Alberta Wildfire reports the largest blaze is out of control about 450 miles north of Edmonton and has burned 887 square miles of land.

The U.S. Environmental Protection Agency rated Helena's air quality as unhealthy Friday morning while the air quality in the Montana cities of Great Falls and Lewistown was rated as unhealthy for sensitive groups such as people with asthma or heart disease. </s> HELENA, Mont. -- Smoke from large wildfires in Canada's Alberta province has drifted into five U.S. states and is causing haze and air quality issues.

More than two dozen fires are burning in Alberta and 10,000 people have been forced from their homes.

The smoke has drifted into Montana, North Dakota, South Dakota, Washington state and Wyoming.

Air quality in Seattle was listed as moderate Friday morning. Eastern and north-central Washington also registered moderate.

The government agency Alberta Wildfire reports the largest blaze is out of control about 450 miles north of Edmonton and has burned 887 square miles of land.

The U.S. Environmental Protection Agency rated Helena's air quality as unhealthy Friday morning while the air quality in the Montana cities of Great Falls and Lewistown was rated as unhealthy for sensitive groups such as people with asthma or heart disease.
• Click here to check air quality near you </s> HELENA, Mont. (AP) — Smoke from large wildfires in Canada's Alberta province has drifted into five U.S. states and is causing haze and air quality issues.

More than two dozen fires are burning in Alberta and 10,000 people have been forced from their homes.

The smoke has drifted into Montana, North Dakota, South Dakota, Washington state and Wyoming.

The government agency Alberta Wildfire reports the largest blaze is out of control about 450 miles (733 kilometers) north of Edmonton and has burned 887 square miles (2,300 square kilometers) of land.

The U.S. Environmental Protection Agency rated Helena's air quality as unhealthy Friday morning while the air quality in the Montana cities of Great Falls and Lewistown was rated as unhealthy for sensitive groups such as people with asthma or heart disease. </s> HELENA, Mont. (AP) - Smoke from large wildfires in Canada's Alberta province has drifted into five U.S. states and is causing haze and air quality issues.

More than two dozen fires are burning in Alberta and 10,000 people have been forced from their homes.

The smoke has drifted into Montana, North Dakota, South Dakota, Washington state and Wyoming.

The government agency Alberta Wildfire reports the largest blaze is out of control about 450 miles (733 kilometers) north of Edmonton and has burned 887 square miles (2,300 square kilometers) of land.

The U.S. Environmental Protection Agency rated Helena's air quality as unhealthy Friday morning while the air quality in the Montana cities of Great Falls and Lewistown was rated as unhealthy for sensitive groups such as people with asthma or heart disease. </s> HELENA, Mont. — Smoke from large wildfires in Canada's Alberta province has drifted into five U.S. states and is causing haze and air quality issues.

More than two dozen fires are burning in Alberta and 10,000 people have been forced from their homes.

The smoke has drifted into Montana, North Dakota, South Dakota, Washington state and Wyoming.

The government agency Alberta Wildfire reports the largest blaze is out of control about 450 miles (733 kilometers) north of Edmonton and has burned 887 square miles (2,300 square kilometers) of land.

The U.S. Environmental Protection Agency rated Helena's air quality as unhealthy Friday morning while the air quality in the Montana cities of Great Falls and Lewistown was rated as unhealthy for sensitive groups such as people with asthma or heart disease.
Air quality warnings are issued for most of Alberta as a result of the thick smoke moving across the province. Places as far south as Calgary have reached 10+ on the Air Quality Health Index, and rated worse than some of the most polluted cities in the world.