St. Catharines: current Air Quality Health Index (AQHI)

Calculated at 9:00 pm EDT Wednesday, April 22, 2026

4

1

2

3

4

5

6

7

8

9

10

+

low risk
(1 - 3)

moderate risk
(4 - 6)

high risk
(7 - 10)

very high risk

Forecast for St. Catharines

• Forecast Air Quality Health Index maximums for St. Catharines
• Issued at: 5:00 pm EDT April 22, 2026

Forecast Air Quality Health Index maximums for St. Catharines

Period	Forecast maximum (Issued at 5:00 pm EDT April 22, 2026)
Wednesday	4 - Moderate Risk
Wednesday night	3 - Low Risk
Thursday	3 - Low Risk

Health message for St. Catharines

• Current Air Quality Health Index: 4
• Calculated at 9:00 pm EDT Wednesday, April 22, 2026
• Risk: Moderate

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.

See the Ontario Ministry of the Environment, Conservation and Parks air quality health messages.

Note: AQHI readings on this web page are based on automatically polled data and have not undergone final verification.