Air quality alert extended through Friday. When will we get rain?

The Southwest Ohio Air Quality Agency has extended the air quality alert through Friday night.

According to the alert, elevated concentrations of particulate matter, which are fine particles caused by pollutants, are expected to reach levels considered unhealthy for sensitive groups due to the wildfires in Canada. Exposure to particulate matter can cause serious problems for the heart and lungs, according to the U.S. Environmental Protection Agency.

The alert is effective from midnight Thursday through 11:59 p.m. Friday.

Areas covered by the alert include Butler, Clermont, Hamilton and Warren counties in Ohio; Boone, Campbell and Kenton counties in Kentucky and Dearborn County in Indiana.

What does an air quality alert mean?

• Take the bus, carpool or walk instead of driving.
• Refuel your vehicle after 6 p.m. Do not top off while refueling and tighten the gas cap.
• Do not idle your vehicle.
• Combine trips, or eliminate unnecessary trips.
• Keep your vehicle maintained with properly inflated tires and timely oil changes.
• Avoid the use of gasoline-powered equipment.
• Avoid the use of oil-based paints and stains.
• Never burn leaves or other yard trimmings.
• Burn clean, seasoned wood in outdoor fire pits, fireplaces and wooden stoves.
• Avoid using fire pits or fireplaces for nonessential home heating.
• Conserve electricity.

What is an air quality alert?

According to Columbia University, the EPA created the air quality index, or AQI, "to monitor and report on air quality each day and let people know about its possible health impacts."

Over 1,000 locations in the United States monitor and record the air for four significant pollutants: ground-level ozone, particulate matter, carbon monoxide and sulfur dioxide. An air quality index level of 100 is considered safe. An AQI under 100 is good or acceptable, and an AQI over 100 is cause for concern, especially for vulnerable groups. Levels over 300 indicate hazardous conditions.

Why is air quality poor in Ohio?

Fires in the eastern Canadian province of Nova Scotia prompted air quality warnings over the weekend in U.S., with a forest fire in New Jersey adding to the air quality issues.

More than 3 million acres have burned in 1,981 fires in Canada so far this year. While one fire has been brought under control, a second fire continues to burn as of Sunday, according to the Associated Press.

Detailed Cincinnati forecast

The National Weather Service predicts dry weather for the Cincinnati region through the end of the week. Chance of rain will arrive Sunday ahead of the next cold front.

Thursday: Sunny, with a high near 78. 

Thursday night: Mostly clear, with a low around 53.

Friday: Sunny, with a high near 81. 

Friday night: Mostly clear, with a low around 54.

Saturday: Sunny, with a high near 85.

Saturday night: Mostly clear, with a low around 59.

Sunday: Showers likely, mainly after 2 p.m. Mostly sunny, with a high near 87. 

Monday: A chance of showers. Partly sunny, with a high near 76. 

Tuesday: A chance of showers. Mostly sunny, with a high near 77.

Wednesday: Mostly sunny, with a high near 83.

Source: National Weather Service, Wilmington.