Thunder Bay - Air Quality Health Index
4Moderate Risk
Moderate Risk
(4-6)
High Risk
(7-10)
Very High Risk
At-Risk Population:
- Consider reducing or rescheduling strenuous activities outdoors if you are experiencing symptoms.
- Find out if you are at risk
General Population:
- No need to modify your usual outdoor activities unless you experience symptoms such as coughing and throat irritation.
Monday
Monday night
Tuesday
Tuesday night
Who is at risk?
People with heart and lung conditions are most affected by air pollution.
To find out if you are at risk, consult the health guide, or your physician.
Visit the national AQHI Web site to learn more about the AQHI.
Did you know...?
Even healthy people can have difficulty breathing on days when the index is high.
The AQHI is an initiative between Environment Canada, Health Canada and the Province of Ontario.

Observed ConditionsFootnote †
4 - Moderate Risk
Calculated at:
11:00 AM EDT Monday 14 July 2025
Forecast Maximums
Issued at:
6:00 AM EDT Monday 14 July 2025
The AQHI is an initiative between Environment Canada, Health Canada and the Province of Ontario.
- Date modified: